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wd40
2013-Jun-19, 08:25 PM
Mars' surface looks quite Earth-like, apart for its utter lifelessness.

If somehow it could be shown with total certitude that there is no type of any life at all anywhere in the entire universe except upon the Earth, apart from deflating some ufologists and Star Trek buffs and rediverting some SETI budgets, how would this change the average astronomer's/cosmologist's/person's worldview, if at all?

slang
2013-Jun-19, 09:03 PM
Closed pending moderator discussion.

ETA: reopened

Paul Beardsley
2013-Jun-20, 05:35 AM
With science and technology as we understand it, we could never be certain that life had not arisen somewhere in a remote part of the universe.

If a technique were to be developed that did indeed allow us to be certain, the existence of that technique, and how it worked, would raise far bigger philosophical problems than the nonexistence of ET life.

swampyankee
2013-Jun-20, 11:31 AM
Considering some of the surprising places life has been found on Earth, as reported here (http://earthsky.org/earth/stephen-giovannoni-discovers-deepest-yet-underground-life), and commentary in articles like this (http://geology.gsapubs.org/content/39/3/287.full), I think that it would be very difficult to conclude, to a high level of confidence, "there is no life on Mars" without a multi-decade survey which includes some pretty deep boreholes. Humanity will not be able to do that sort of research before there is routine interplanetary travel, something I do not foresee within a century.

Multiply that sort of effort by every major body, even restricted to those which may have liquid water within a few tens of meters of their surfaces, and one can see the sort of effort required to conclude, with a high level of confidence, the statement "within our Solar System, life only exists on Earth."

Noclevername
2013-Jun-20, 01:10 PM
If somehow it could be shown with total certitude that there is no type of any life at all anywhere in the entire universe except upon the Earth, apart from deflating some ufologists and Star Trek buffs and rediverting some SETI budgets, how would this change the average astronomer's/cosmologist's/person's worldview, if at all?

For us to conclude that accurately, would mean that we have explored in great detail every part of the entire Universe, which would certainly have a great impact on all the physical sciences; not to mention that to do so, we'd need a very successful open-ended economy and massively advanced technology, signifigantly affecting the entire human population.

Spacedude
2013-Jun-20, 02:24 PM
How would it change things? Not much. For one thing we wouldn't have to change our usual human behavior. We'd just go on and exploit the rest of the universe as planned without worrying about competition.

But we're asking the wrong question : "Can other life exist in the universe?"
The real question should be "Can life exist in the universe?"
We already have the answer.

iquestor
2013-Jun-20, 03:09 PM
The OP Assumes it would be possible to conclusively know that Life was unique to Earth alone, and then asks, what would the impact be on our worldview.

I understand how impossible it would be to prove such a conclusive statement, however for now Ill suspend my objections because it is a very interesting question...

Personally, I think it would be a punch to the gut for a lot of humanity. Why is Science Fiction such a popular genre? because of the Aliens. Try to name a single Science Fiction story or movie that didnt invoke alien life. I am sure there are a few somewhere, but nothing comes to mind. The idea of ET Life is central to humanity because it is closely tied into our place in the universe and gives some hope for the future. If Life is Out there, then we have a future in Space; that it means there are some planets with biospheres, atmospheres, liquid water, temperate climates. , and may find other places humanity can live comfortably, and find other friends who are the product of different evolutionary processes. We can outlive the Earth itself. We aren't doomed when Earth dies.

Without the possibility of Life elsewhere, Humanity, indeed all earthlife, becomes very, very special in that Earth is unique in the entire universe. I think it would be very, very depressing to many (me, for one) and would likely stifly manned space missions as well as numerous scientific studies. I think it would also have an impact on the worlds Religion because it might seem to support the presence of Intelligent Creation, and therefore affect many peoples beliefs.

Noclevername
2013-Jun-20, 04:54 PM
If Life is Out there, then we have a future in Space; that it means there are some planets with biospheres, atmospheres, liquid water, temperate climates. , and may find other places humanity can live comfortably, and find other friends who are the product of different evolutionary processes. We can outlive the Earth itself. We aren't doomed when Earth dies.

I don't think lack of ET life would hinder our ability to survive off-Earth, we'd have plenty of room and resources to build artificial biospheres without worrying about displacing any native life. I'd even go so far as to say that it might be easier (or at least simpler) to make our own "worlds" to suit our needs, than to try to adapt to a completely alien biosphere.

iquestor
2013-Jun-20, 05:42 PM
I don't think lack of ET life would hinder our ability to survive off-Earth, we'd have plenty of room and resources to build artificial biospheres without worrying about displacing any native life. I'd even go so far as to say that it might be easier (or at least simpler) to make our own "worlds" to suit our needs, than to try to adapt to a completely alien biosphere.

My Assumption is that if there is Life out there then there are Biospheres that are in some ways similar to Earth. It takes life to create the kind of atmosphere we have, and biology also contributes in many ways to stabilize climate.

With life, (I assume) we are far more likely to find worlds where temperature is stabilized and there are natural sources of water anf other resources that arent frozen solid or boiling hot.

Without life we would have a much tougher time of it because we would need self sustaining micro worlds that take care of every need we have, and not put us in danger if something failed.

I think it would be much easier to live on a planet where we could walk outside with only a light bodysuit (or less) for protection and a way to breathe, rather than have going outside be a tie between freezing/boiling, suffocation and rapid decompression.

If there is life then we could also adapt offspring to live on the world and become part of its biology, if necessary.

If we knew for certain that there was no life anywhere else in the universe, then I doubt seriously there will ever be any effort for humanity to travel to another Star.

If there is life, especially the discovery of a living biosphere and or intelligence around another star, I think we would certainly try to develop the technology to go there, or at least find a way to communicate and share knowledge over interstellar distances.
If there is not, I doubt we will ever even try, there would be little point. This is why I say it would have a great impact on humanity.

JustAFriend
2013-Jun-20, 05:52 PM
With hundreds of millions of planets in each galaxy and hundreds of billions of galaxies (or more), you're going to have to do a LOT of proving that there is no life anywhere else...

Wolf-S
2013-Jun-20, 06:30 PM
I'll write from my perspective.

First of all, it would be hard for me to believe it, since such an extraordinary claim requires extraordinary evidence. I have a hard time imagining sufficient evidence that would prove that life on Earth is the only one in the (observable or whole) Universe once and for all.

I'm thinking that this method of proof itself may be so extraordinary that it would affect my world view more so than knowledge of the existence/non-existence of life. I'm going to give two, to my mind, different examples.

Example 1: We find a way to go into indestructible, all-sensory observer mode at FTL and observe millions, billions of planets. Perhaps the insides of the planets. Cores of stars. Black holes, even. Perhaps peek into the nanoworld and look for life there, however improbable it may seem. We have to include everything. Even time. Go back and forward in time - who knows, maybe universe was going wild with life at the time of first generation stars?

Then the probability that Earth life is the only one may start to approach 100% (and it may never reach it this way).

If done for quite some time and life is still not found, it would make me think of a waste of space. It does not answer any questions about possible importance to life, we just look and don't find anything. Technology behind searching is great, but does it make me look at life as something ridiculously important on the scale of Universe? No, since there are no reason to believe that.

Example 2: We find a higher universe's log stream of symbols (in ternary!) that, when deciphered, is found to contain very precise information about our universe. Amongst many things about dark matter, big bang at t = 0 and such, it contains precise information of all locations of all living beings. It's sufficiently researched and it is found that a team of scientists from the higher universe had planted the seed!

Well, now there is sufficient proof that we are kind of important on the scale of our universe. However, it does not and cannot answer all of the questions. What if yet higher universe's molluscs had had telepathically forced those scientists to plant the seed? And so on.)

iquestor
2013-Jun-20, 06:54 PM
The OP Is about the ramifications of a proof that Life is unique to Earth, then asks what the impact of that would be on Humanity.

It isn't asking whether such a proof is possible (it isn't) , its part of the assumption, so I think you have to ignore that the proof is impossible, assume it's true, then address the question asked.

mkline55
2013-Jun-20, 07:06 PM
I think a number of conspiracy theorists would have something added to their lists of conspiracies. "Proof?! Ha! That is not proof! You are hiding something." That sort of talk.

iquestor
2013-Jun-20, 07:14 PM
absolutely. I dont think we can even prove there isnt life on Mars as someone pointed out, without a century of rigorous study.

Paul Beardsley
2013-Jun-20, 10:15 PM
Why is Science Fiction such a popular genre? because of the Aliens. Try to name a single Science Fiction story or movie that didnt invoke alien life. I am sure there are a few somewhere, but nothing comes to mind.

Er, The Time Machine, The Invisible Man, Dying Inside, The Stochastic Man, Voyage, The Foundation trilogy, Neuromancer, The Day of the Triffids, Cats Cradle, Flowers for Algernon... and that's just the better-known novels.

Noclevername
2013-Jun-20, 10:22 PM
If there is not, I doubt we will ever even try, there would be little point.

I disagree, life is not the only motivation to see the rest of the universe. There's plenty of other things to see and lots of other unknowns to discover.

Paul Beardsley
2013-Jun-20, 10:27 PM
It isn't asking whether such a proof is possible (it isn't) , its part of the assumption, so I think you have to ignore that the proof is impossible, assume it's true, then address the question asked.

I get what you are saying, but it's ignoring the way science works. Science isn't about what is true so much as what we can know. For people to accept the proof of something unprovable, our mindset would have to change so thoroughly that the question becomes moot.

It's a bit like accepting a ghost's word that there is no afterlife.

A possibly more interesting scenario would be if we had a pretty good idea of how abiogenesis worked, and we were able to predict with confidence that a fairly large number of specific worlds should be teeming with life, but each time we get around to exploring one of them it turns out to be barren, leading us to believe that the universe is probably empty.

Colin Robinson
2013-Jun-20, 11:28 PM
Mars' surface looks quite Earth-like, apart for its utter lifelessness.

If somehow it could be shown with total certitude that there is no type of any life at all anywhere in the entire universe except upon the Earth, apart from deflating some ufologists and Star Trek buffs and rediverting some SETI budgets, how would this change the average astronomer's/cosmologist's/person's worldview, if at all?

One very important difference between Earth and Mars is that liquid water is hard to find on Mars today, although Mars seems to have had a lot more water a few billion years ago.

But Mars and Earth together are a very small fraction of the total number of planets and moons in the universe.

If you could prove to me that none of the other worlds have life, I would then want to ask you: What do they have? What sorts of things happen on worlds which, like Earth, are chemically and meteorologically active? What sorts of systems, if any, emerge on worlds like that? If not life, what?

Colin Robinson
2013-Jun-21, 01:51 AM
I get what you are saying, but it's ignoring the way science works. Science isn't about what is true so much as what we can know. For people to accept the proof of something unprovable, our mindset would have to change so thoroughly that the question becomes moot.

It's a bit like accepting a ghost's word that there is no afterlife.

A possibly more interesting scenario would be if we had a pretty good idea of how abiogenesis worked, and we were able to predict with confidence that a fairly large number of specific worlds should be teeming with life, but each time we get around to exploring one of them it turns out to be barren, leading us to believe that the universe is probably empty.

Then, returning to the OP's question, in a modified form:

If somehow it could be shown as highly probable that there is no type of any life at all anywhere in the entire universe except upon the Earth, how would this change the average astronomer's/cosmologist's/person's worldview, if at all?

Selfsim
2013-Jun-21, 01:57 AM
Mars' surface looks quite Earth-like, apart for its utter lifelessness.

If somehow it could be shown with total certitude that there is no type of any life at all anywhere in the entire universe except upon the Earth, apart from deflating some ufologists and Star Trek buffs and rediverting some SETI budgets, how would this change the average astronomer's/cosmologist's/person's worldview, if at all?Considering some of the surprising places life has been found on Earth, as reported here, and commentary in articles like this, I think that it would be very difficult to conclude, to a high level of confidence, "there is no life on Mars" ...It seems clear to me that at present, our collective worldview of exo-life, is presently purely shaped by opinion based science.

After all, there is no data whatsoever on exo-life, at all, and yet there is a clear collective desire to have exo-life exist.

Any 'total certitudes' coming from science, are seconded into that preconceived worldview, to justify the 'likelihood of exo-life's existence'.

Therefore any 'total certitudes' about exo-life, one way or the other, would simply be forced to fit into that same unchanging thought pattern.

The truism underlined above, serves as the exclamation mark on the unreasonable bias stemming from this seemingly endemic, invariant affliction.

Selfsim
2013-Jun-21, 02:06 AM
… If somehow it could be shown as highly probable that there is no type of any life at all anywhere in the entire universe except upon the Earth, how would this change the average astronomer's/cosmologist's/person's worldview, if at all? … then the conversation would be about the slight probability that life exists, other than on Earth.

Bobunf
2013-Jun-21, 02:55 AM
If a theory of abiogenesis were to emerge which showed that the probability of life originating on any world was 1 in 10^1000, that would pretty much establish the OP assumption as fact. However, such a theory is not in sight.

Another way to get at such consequences is to consider the opposite. How would it affect our species if we were to discover an exoplanet with an Earth-like temperature, water vapor, ozone, methane, and nitric oxides out of thermal equilibrium? Maybe a little chlorophyll?

I think finding life in the solar system would not be as significant unless it could be shown that it was not related to Earth life. It is surprising that no Earth life has been found on Mars.

Colin Robinson
2013-Jun-21, 03:33 AM
The OP Assumes it would be possible to conclusively know that Life was unique to Earth alone, and then asks, what would the impact be on our worldview.

I understand how impossible it would be to prove such a conclusive statement, however for now Ill suspend my objections because it is a very interesting question...

Personally, I think it would be a punch to the gut for a lot of humanity. Why is Science Fiction such a popular genre? because of the Aliens. Try to name a single Science Fiction story or movie that didnt invoke alien life.

Then again some of the most popular science fiction involves aliens who are a lethal threat to humanity. E.g. War of the Worlds, the Kraken Wakes, Killing Star.


I am sure there are a few somewhere, but nothing comes to mind. The idea of ET Life is central to humanity because it is closely tied into our place in the universe and gives some hope for the future. If Life is Out there, then we have a future in Space; that it means there are some planets with biospheres, atmospheres, liquid water, temperate climates. , and may find other places humanity can live comfortably, and find other friends who are the product of different evolutionary processes.

If life is out there, we may find either friends or enemies. Or living things which are not that interested in us, either way.

If there are no other life-forms out there, it means the universe is ours for the taking, if we want it and can develop the technology. I've read serious articles by people who like that scenario.

Arnold Rimmer
2013-Jun-21, 01:36 PM
Try to name a single Science Fiction story or movie that didnt invoke alien life. I am sure there are a few somewhere, but nothing comes to mind.


Er, The Time Machine, The Invisible Man, Dying Inside, The Stochastic Man, Voyage, The Foundation trilogy, Neuromancer, The Day of the Triffids, Cats Cradle, Flowers for Algernon... and that's just the better-known novels.

Also Red Dwarf.
If I remember correctly all the living things they encounter are human made genetically engineered life-forms (GELFS).

LookingSkyward
2013-Jun-21, 01:36 PM
Also Red Dwarf.
If I remember correctly all the living things they encounter are human made genetically engineered life-forms (GELFS). Yep.

swampyankee
2013-Jun-21, 02:00 PM
Er, The Time Machine, The Invisible Man, Dying Inside, The Stochastic Man, Voyage, The Foundation trilogy, Neuromancer, The Day of the Triffids, Cats Cradle, Flowers for Algernon... and that's just the better-known novels.

Almost everything by Asimov (possibly apocryphal story is that John W Campbell would not accept any story where humans were not on top; Asimov had written a story where humans weren't that Campbell rejected, so he simply eliminated aliens from almost all his stories).

iquestor
2013-Jun-21, 02:51 PM
Er, The Time Machine, The Invisible Man, Dying Inside, The Stochastic Man, Voyage, The Foundation trilogy, Neuromancer, The Day of the Triffids, Cats Cradle, Flowers for Algernon... and that's just the better-known novels.

OK, point taken. I should have said, Space themed SciFi. there are some that dont include ET Life, but not many.

mkline55
2013-Jun-21, 07:49 PM
Mars' surface looks quite Earth-like, apart for its utter lifelessness.

If somehow it could be shown with total certitude that there is no type of any life at all anywhere in the entire universe except upon the Earth, apart from deflating some ufologists and Star Trek buffs and rediverting some SETI budgets, how would this change the average astronomer's/cosmologist's/person's worldview, if at all?
That is a lot deeper question than it appears at first, and it is quite easy to get sidetracked. I'll try to stay on point.

A lot would depend on how that information was obtained. Obviously, if there are no ETs, then no ET of any sort could have shared that information, unless it was just a note left behind which told us that they had destroyed all other life forms except that on Earth, then destroyed themselves as well. Does ET include all classes of supreme beings? Other possible ways to make that uniqueness determination might include the discovery of a one-time principle for the basis of life, or the discovery that all the rest of the universe is really just an illusion, or the completion of a thorough exploration of the entire universe.

Purely from an astronomical/cosmological view, it makes no difference. From a personal/human view, I would expect to see a wide spectrum of worldviews.

For someone who is hoping for some form of rescue by ETs, there would be some degree of despair.

For someone who fears ETs, there is salvation.

For someone seeking a universal community, there's disappointment.

For someone hoping to expand life to other stars, there's room for expansion (except if the universe is an illusion), and no fear of contamination or of competition.

For someone who didn't care in the first place, there's the chance to gloat.

Colin Robinson
2013-Jun-23, 05:51 AM
It occurs to me that if it were discovered (somehow) today or tomorrow that the universe had no life anywhere except Earth, people who were alive in the early sixties would experience a sense of deja vu.

It would remind them of when the first space probes to Venus revealed the extreme heat of its surface, and the first missions to Mars photographed moon-like craters, and sudden death came to the widespread dreams about non-microbial Venusians and Martians.

Earth, Mars and Venus are a very small fraction of the number of planets in the universe, however back in the sixties they were a big fraction of then-known planets. And Mars and Venus were considered the two planets beyond Earth most likely to hold life. So the news from the space probes was serious stuff.

swampyankee
2013-Jun-23, 03:52 PM
I'm willing to accept the non-existence of UFOs1 based on the constraints imposed by physical law and the unreliability of eye witness testimony. I view the non-existence of extraterrestrial life as an entirely separate question, and linking the two to be completely specious.

----------------

1: Using "UFO" in its current sense as space ships from afar.

Swift
2013-Jun-23, 04:29 PM
It occurs to me that if it were discovered (somehow) today or tomorrow that the universe had no life anywhere except Earth, people who were alive in the early sixties would experience a sense of deja vu.

I can't speak for all people who were alive in the early sixties, but as one of those people, I would have no sense of deja vu. Even then I don't recall ever thinking that the discoveries you mention meant that we were the only life in the Universe. But then, I frankly can't imagine any way the "what if" proposed in the OP could ever come out, it seems beyond fantasy to me.


I'm willing to accept the non-existence of UFOs1 based on the constraints imposed by physical law and the unreliability of eye witness testimony. I view the non-existence of extraterrestrial life as an entirely separate question, and linking the two to be completely specious.

----------------

1: Using "UFO" in its current sense as space ships from afar.
Yes

swampyankee
2013-Jun-23, 10:49 PM
It seems clear to me that at present, our collective worldview of exo-life, is presently purely shaped by opinion based science.

After all, there is no data whatsoever on exo-life, at all, and yet there is a clear collective desire to have exo-life exist.

Any 'total certitudes' coming from science, are seconded into that preconceived worldview, to justify the 'likelihood of exo-life's existence'.

Therefore any 'total certitudes' about exo-life, one way or the other, would simply be forced to fit into that same unchanging thought pattern.

The truism underlined above, serves as the exclamation mark on the unreasonable bias stemming from this seemingly endemic, invariant affliction.

We know that. This is speculation (http://www.wordcentral.com/cgi-bin/student?book=Student&va=speculation).

Jens
2013-Jun-23, 11:00 PM
As somebody else mentioned, I can only think of two ways for us to gain that knowledge. One would be for a creator to tell us so, and the other would be for us to learn that everything beyond the earth is an illusion. I think either of those would have a serious effect on our outlook.

Colin Robinson
2013-Jun-23, 11:31 PM
I can't speak for all people who were alive in the early sixties, but as one of those people, I would have no sense of deja vu. Even then I don't recall ever thinking that the discoveries you mention meant that we were the only life in the Universe. But then, I frankly can't imagine any way the "what if" proposed in the OP could ever come out, it seems beyond fantasy to me.

Like you, I can't imagine how we could reach certainty that there's no other life in the universe. Although I can imagine a scenario that might lead us to think the universe except for Earth is very probably empty of life, namely:

* if we reached a pretty good idea of how abiogenesis happened,
* and it turned out to require a combination of say 30 necessary pre-conditions, each independent of the other pre-conditions,
* and each of the 30 pre-conditions has a probability of say 1 in 10 on any given Earth-like planet.

Then we might conclude that the chances of life emerging on any given Earth-like planet is of the order of 1 in 10 to the power of 30.

Odds like that would lead to the conclusion that another abiogenesis is highly improbable anywhere else among the billions of galaxies in the observable universe.

So perhaps the OP's question could be reworked in a less fantastic form:

If it could be shown as highly improbable that there is any type of any life at all anywhere in the entire universe except upon the Earth, how would this change the average astronomer's/cosmologist's/person's worldview, if at all?

iquestor
2013-Jun-23, 11:47 PM
Like you, I can't imagine how we could reach certainty that there's no other life in the universe. Although I can imagine a scenario that might lead us to think the universe except for Earth is very probably empty of life, namely:

* if we reached a pretty good idea of how abiogenesis happened,
* and it turned out to require a combination of say 30 necessary pre-conditions, each independent of the other pre-conditions,
* and each of the 30 pre-conditions has a probability of say 1 in 10 on any given Earth-like planet.

Then we might conclude that the chances of life emerging on any given Earth-like planet is of the order of 1 in 10 to the power of 30.

Odds like that would lead to the conclusion that another abiogenesis is highly improbable anywhere else among the billions of galaxies in the observable universe.

So perhaps the OP's question could be reworked in a less fantastic form:

If it could be shown as highly improbable that there is any type of any life at all anywhere in the entire universe except upon the Earth, how would this change the average astronomer's/cosmologist's/person's worldview, if at all?

That changes the whole thing. Just because we understand 1 process of abiogenesis does not mean there aren't others that we cant imagine.

Also I think you guys are completely missing the point of the OPs question. It's asking about the human psychological response to learning there definately is no life elsewhere, and how it would affect professionals, courses of research, as well as the average Joes response. Its a pretty deep question.

Swift
2013-Jun-24, 12:26 AM
Also I think you guys are completely missing the point of the OPs question. It's asking about the human psychological response to learning there definately is no life elsewhere, and how it would affect professionals, courses of research, as well as the average Joes response. Its a pretty deep question.
Again, only speaking for myself, but that is exactly what I thought wd40 meant. And I guess it would have an impact on human behavior and thought. But it is such a far fetched proposition, in my opinion, that I can't fathom what particular impact it would have.

And I suppose, for a certain percentage of humans - those who already believe this, or who are just struggling every day to survive and don't have time for such thoughts, it would have no real impact at all.

wd40, what do you think the impact would be?

Colin Robinson
2013-Jun-24, 01:07 AM
That changes the whole thing. Just because we understand 1 process of abiogenesis does not mean there aren't others that we cant imagine.

Valid point.

Nonetheless, research on abiogenesis seems to me the most plausible way that we might get a handle on the probability of life on a given planet, and the probable overall density or scarcity of life in the universe, without actually inspecting every planet.


Also I think you guys are completely missing the point of the OPs question. It's asking about the human psychological response to learning there definately is no life elsewhere, and how it would affect professionals, courses of research, as well as the average Joes response. Its a pretty deep question.

Would the psychological response to a definite negative be so different from the psychological response to a negative based on extreme improbability?

I'm imagining a father and a son looking up at the stars:

Son: Do you think there is life out there.
Father: No. The latest scientific findings say there can't be.

or

Son: Do you think there is life out there.
Father: Almost certainly no. The latest scientific findings say that the odds against that are one in a grillion.

Would the psychological effect on the son of these two answers be so different?

Paul Wally
2013-Jun-24, 02:11 AM
Mars' surface looks quite Earth-like, apart for its utter lifelessness.

If somehow it could be shown with total certitude that there is no type of any life at all anywhere in the entire universe except upon the Earth, apart from deflating some ufologists and Star Trek buffs and rediverting some SETI budgets, how would this change the average astronomer's/cosmologist's/person's worldview, if at all?

If by "shown" you mean discovering it as a brute empirical fact, then I guess the response of astronomers, cosmologists and other scientists would be to try and understand why the emergence of life is such an extremely unlikely phenomenon. I don't think such a finding would affect the so called ordinary person
much. The default view is geocentrism anyway, so it will just be a regress back to old times. It won't even make front page news, maybe a short article on page 8: "Scientist proves aliens don't exist".

Jens
2013-Jun-24, 03:04 AM
I'm imagining a father and a son looking up at the stars:

Son: Do you think there is life out there.
Father: No. The latest scientific findings say there can't be.



Even in that case, I can imagine two (at least) possibilities for the son's response, depending on whether he was watching ET or Starship Trooper the night before.

(ET): Oh, bummer!
(Starship Trooper): Great!

Selfsim
2013-Jun-24, 03:16 AM
We know that.Then you would also know that scientific speculation is framed by its testability, substantive priors and theoretical compliance .. whereas the OP premise, is not?

And therefore this premise, would not be viewed as the precondition, or resultant, of scientific speculation .. It is a complete fantasy, with an accompanying query as to others' opinions ..


This is speculation (http://www.wordcentral.com/cgi-bin/student?book=Student&va=speculation).Just not scientifically relevant speculation ...

The average astronomer's/cosmologist's/person's worldview of its ramifications, would therefore depend on their understanding of how science, and the knowledge it gathers, actually works … (as distinct from how they think it works) ...

Selfsim
2013-Jun-24, 03:37 AM
If by "shown" you mean discovering it as a brute empirical fact, ..I think a hypothetical mathematical model, which discloses its assumptions, might be feasible. The assumptions would then be debatable. In the absence of empirical evidence, (such as another instance of life elsewhere), the conclusions from such a model, can also be shown to be almost entirely dependent on the 'going-in' initial assumptions.


The default view is geocentrism anyway..Well, I would say the default view is defined as geocentric.
The "ism" part is optional, and would be a matter of personal taste, however ..

Ara Pacis
2013-Jun-24, 06:13 AM
Mars' surface looks quite Earth-like, apart for its utter lifelessness.

If somehow it could be shown with total certitude that there is no type of any life at all anywhere in the entire universe except upon the Earth, apart from deflating some ufologists and Star Trek buffs and rediverting some SETI budgets, how would this change the average astronomer's/cosmologist's/person's worldview, if at all?

Religions would see an uptick in popularity because Parsimony would be on their side.

Then we'd go to the stars because it's Manifest Destiny all over again, with no natives to push out of the way.

ASTRO BOY
2013-Jun-24, 10:57 AM
Mars' surface looks quite Earth-like, apart for its utter lifelessness.

If somehow it could be shown with total certitude that there is no type of any life at all anywhere in the entire universe except upon the Earth, apart from deflating some ufologists and Star Trek buffs and rediverting some SETI budgets, how would this change the average astronomer's/cosmologist's/person's worldview, if at all?



It would be interesting to know what form this "somehow"could take, in a Universe near infinite in size and content. In that respect, such a "certitude" would in my opinion be impossible.
But there's no harm in speculation, and not being a UFOlogist nor being a Star Trek buff [well at least not to the extent of wearing costumes and making up] and not having affiliation with SETI, I would be somewhat amazed if such a thing were to be shown, and would probably confront my local Bishop and ask for my excommunication to be reversed.
I would then probably join with some religious order and wear sandles with a rope for a belt.

iquestor
2013-Jun-24, 02:26 PM
Valid point.

Nonetheless, research on abiogenesis seems to me the most plausible way that we might get a handle on the probability of life on a given planet, and the probable overall density or scarcity of life in the universe, without actually inspecting every planet.



Would the psychological response to a definite negative be so different from the psychological response to a negative based on extreme improbability?

I'm imagining a father and a son looking up at the stars:

Son: Do you think there is life out there.
Father: No. The latest scientific findings say there can't be.

or

Son: Do you think there is life out there.
Father: Almost certainly no. The latest scientific findings say that the odds against that are one in a grillion.

Would the psychological effect on the son of these two answers be so different?

I think it would be simply because the univrse is SO BIG! Take for instance The Drake Equation; you can plug in very modest, conservative estimates for each variable and STILL Come up with thousands of ETI in this galaxy alone. Now expand that to the bllions of galaxies that exist. If there were only 1 abiogenesis per galaxy, we would still have billions of ETI Civs.

Therefore, even a very very very very very one-in-a-bazillion chance of abiogenesis would still leave open the high possibility of ETI somewhere else in the universe.

thats why I say only a definite answer would satisfy what the OP is getting at. the psychological impact of knowing we are alone is different that the psycholigical impact of know we are probably alone.

MaDeR
2013-Jun-24, 02:39 PM
If somehow it could be shown with total certitude that there is no type of any life at all anywhere in the entire universe except upon the Earth, apart from deflating some ufologists and Star Trek buffs and rediverting some SETI budgets, how would this change the average astronomer's/cosmologist's/person's worldview, if at all?

Let's assume that "there is no type of any life at all anywhere in the entire universe except on the Earth". I will set aside means to achieve knowledge that would allowed this assumption - it is entirely different problem.

As our knowledge about universe, laws of physics etc indicate life should be normal byproduct of ths universe functioning, no life whatsoever would present some certain enormous consequences, up and including us being simulation or otherwise in some sense "artifical" or "unreal".

iquestor
2013-Jun-24, 03:36 PM
Let's assume that "there is no type of any life at all anywhere in the entire universe except on the Earth". I will set aside means to achieve knowledge that would allowed this assumption - it is entirely different problem.

As our knowledge about universe, laws of physics etc indicate life should be normal byproduct of ths universe functioning, no life whatsoever would present some certain enormous consequences, up and including us being simulation or otherwise in some sense "artifical" or "unreal".

We cannot reach the conclusion that "life should be a normal by-product of the universe functioning". We only have 1 example.

If we were to somehow find that we are the only life, then perhaps the creation aspects of many religions would certainly gain a boost from this new knowledge.

To me, I doubt there can be one and only instance of anything in a universe so big. IMO, That would be the extraordinary conclusion.

wd40
2013-Jun-24, 03:58 PM
I didn't realise my question was so 'deep'!

If life outside of the Earth was somehow shown definitely not to exist, it would among other things:

1. Bring about the demise of the Dr Who (not all episodes), Star Wars and Star Trek genre which have so influenced and entertained everyone in the world under 60, with ET science fiction becoming in people's minds not even a flight of fancy about something that never was nor ever will be.

2. Spur non-extraterrestrial explanations for UFOs.

3. Spur debate between Creationists and Evolutionists as to whether the non-existence of extraterrestrial life supported their respective view, or had no impact either way.

4. Possibly raise humanity's self-esteem in some way, whilst unsettling others.

swampyankee
2013-Jun-24, 04:48 PM
I didn't realise my question was so 'deep'!

If life outside of the Earth was somehow shown definitely not to exist, it would among other things:

1. Bring about the demise of the Dr Who (not all episodes), Star Wars and Star Trek genre which have so influenced and entertained everyone in the world under 60, with ET science fiction becoming in people's minds not even a flight of fancy about something that never was nor ever will be.

2. Spur non-extraterrestrial explanations for UFOs.

3. Spur debate between Creationists and Evolutionists as to whether the non-existence of extraterrestrial life supported their respective view, or had no impact either way.

4. Possibly raise humanity's self-esteem in some way, whilst unsettling others.

1: It's fiction; the only people who'd care are the ones who get cranky when anything more speculative than the Sun rising in the east is mentioned.

2: Most of the UFO advocates are going to disbelieve the evidence against ET anyway.

3: Creationists don't debate; they lie. "Debate" implies a certain respect for evidence that Creationists lack.

4: It doesn't need raising; it probably needs to be taken down a notch.

;)

swampyankee
2013-Jun-24, 07:24 PM
Then you would also know that scientific speculation is framed by its testability, substantive priors and theoretical compliance .. whereas the OP premise, is not?

And therefore this premise, would not be viewed as the precondition, or resultant, of scientific speculation .. It is a complete fantasy, with an accompanying query as to others' opinions ..

Just not scientifically relevant speculation ...

The average astronomer's/cosmologist's/person's worldview of its ramifications, would therefore depend on their understanding of how science, and the knowledge it gathers, actually works … (as distinct from how they think it works) ...

Gee, I'm feeling well and thoroughly chastised. I'll have to remember to avoid any discussions on a speculative topic, which cannot be tested in any meaningful way with foreseeable technology in a non-academic forum.

Selfsim
2013-Jun-24, 09:18 PM
... and rediverting some SETI budgets, how would this change the average astronomer's/cosmologist's/person's worldview, if at all?I'm wondering how 'worldviews' would change, if for some reason, SETI finally 'got the chop'? (At least this question doesn't involve any particularly unphysical premise .. and yet, I suspect it still invokes the same emotional response as the OP scenario).

For example, would the community then turn, and look at Carl Sagan as being someone who perpetrated a massive deception, using science as the means? (Sagan being the Grand-Dad of SETI, that is).

Paul Wally
2013-Jun-24, 10:20 PM
I'm wondering how 'worldviews' would change, if for some reason, SETI finally 'got the chop'?

That could happen for a number of different reasons, none of which would have anything to do with whether aliens exist or not.


For example, would the community then turn, and look at Carl Sagan as being someone who perpetrated a massive deception, using science as the means? (Sagan being the Grand-Dad of SETI, that is).

Huh?? If it was a "massive deception" then Sagan must have known something that we don't, for example that aliens don't really exist. But how could he have known such a thing?

slang
2013-Jun-24, 10:45 PM
1. Bring about the demise of the Dr Who (not all episodes), Star Wars and Star Trek genre which have so influenced and entertained everyone in the world under 60, with ET science fiction becoming in people's minds not even a flight of fancy about something that never was nor ever will be.

Would it? The fantasy genre does pretty well, despite that by now we've shown that there is no magic, there are no elves, pixies don't hop on hero's shoulder, no trolls (well, not those in the books, we got plenty of the other type around), no other worlds bodily accessible through dreams, no speaking axes, no Ents, no Nac Mac Feegle (ach, crivens!), etc. etc.

ASTRO BOY
2013-Jun-24, 10:57 PM
I'm wondering how 'worldviews' would change, if for some reason, SETI finally 'got the chop'? (At least this question doesn't involve any particularly unphysical premise .. and yet, I suspect it still invokes the same emotional response as the OP scenario).

For example, would the community then turn, and look at Carl Sagan as being someone who perpetrated a massive deception, using science as the means? (Sagan being the Grand-Dad of SETI, that is).



The two horrid variables of politics and economics will only ever slow down the real prospects of looking and going where we have not gone before.
Either or neither of the two will ever permantley halt that aspect of human culture until we know and meet all there is to know and meet.
Not really sure about what deception you are referring to, as the great educator referred to, always proceeded with the utmost logic and reasonable assumptions.

publiusr
2013-Jun-24, 10:58 PM
I am hoping no life is found on Mars, or missions there will be curtailed I should think.

Selfsim
2013-Jun-24, 11:34 PM
That could happen for a number of different reasons, none of which would have anything to do with whether aliens exist or not. Well, those reasons may not be specifically about 'whether aliens exist or not', but I think the 'iconic alien' certainly provokes deeper questions about imagination vs reality. Could it be that SETI's funding demise represents the emergence of the view that aliens are divorced from the concerns of the average Joe's everyday reality, (and hence, largely irrelevant)?

Huh?? If it was a "massive deception" then Sagan must have known something that we don't, for example that aliens don't really exist. But how could he have known such a thing?Sagan was certainly known for his 'popularization' of science and for his efforts to increase scientific understanding among the general public. He took positions in favor of scientific skepticism and against pseudoscience … and yet, the search for aliens is very much dominated by a hypothesis which asserts the possibility of their existence to be true.

I'd call that a kind of deception .. and although it certainly was not what Sagan stood for .. it could be argued that this is the perception of what his work eventually evolved into via SETI (and its successor, Astrobiology).

Paul Wally
2013-Jun-25, 12:00 AM
1. Bring about the demise of the Dr Who (not all episodes), Star Wars and Star Trek genre which have so influenced and entertained everyone in the world under 60, with ET science fiction becoming in people's minds not even a flight of fancy about something that never was nor ever will be.


The intro to Star Wars could just be changed to : "In a universe far far away ..."

That would be a universe where life is (supposedly) much much more probable than this one. This brings to mind the anthropic principle.
What would a universe where the emergence of life is extremely improbable look like? Does this look like such universe?
Or, what would a universe look like where life is impossible? Nobody knows, 'cause there's nobody there to see what it looks like.
So, we must be in a universe where life has at least a non-zero probability of emerging.

ASTRO BOY
2013-Jun-25, 12:10 AM
Sagan was certainly known for his 'popularization' of science and for his efforts to increase scientific understanding among the general public. He took positions in favor of scientific skepticism and against pseudoscience … and yet, the search for aliens is very much dominated by a hypothesis which asserts the possibility of their existence to be true.


He was as history shows'a great scientist and educator who knew the benefit of Imagination as well as knowledge in science and how they always will go hand in hand. He of course had both of those qualities.





I'd call that a kind of deception .. and although it certainly was not what Sagan stood for .. it could be argued that this is the perception of what his work eventually evolved into via SETI (and its successor, Astrobiology).





Not by any stretch of the imagination.....more along the lines of scientific deduction and logical assumptions.

Paul Wally
2013-Jun-25, 01:55 AM
Could it be that SETI's funding demise represents the emergence of the view that aliens are divorced from the concerns of the average Joe's everyday reality, (and hence, largely irrelevant)?

You mean the David Drumlin worldview?


... yet, the search for aliens is very much dominated by a hypothesis which asserts the possibility of their existence to be true.

That possibility follows logically from the fact that we exist in this universe, so I wouldn't really classify that as an hypothesis.


I'd call that a kind of deception .. and although it certainly was not what Sagan stood for .. it could be argued that this is the perception of what his work eventually evolved into via SETI (and its successor, Astrobiology).

I don't see why it would be interpreted as "deception". Even if Carl Sagan were, by some logic-defying feat, proven wrong about believing that alien life is possible, why would being wrong about something be interpreted as being deceptive?

Selfsim
2013-Jun-25, 02:53 AM
You mean the David Drumlin worldview?Ahh .. yes … the courageous hero in 'Contact'? :p :)


That possibility follows logically from the fact that we exist in this universe, so I wouldn't really classify that as an hypothesis.Yeah .. its more like a metaphysical postulate .. which we all know can quite easily turn out to be completely wrong.


I don't see why it would be interpreted as "deception". Even if Carl Sagan were, by some logic-defying feat, proven wrong about believing that alien life is possible, why would being wrong about something be interpreted as being deceptive?Such seems to be the evolving public expectation of science professionals (http://www.livescience.com/27738-laquila-seismologists-appeal-manslaughter-verdict.html) being paid for their opinions.

ASTRO BOY
2013-Jun-25, 09:04 PM
One thing for sure, if that very unlikely scenario of us being alone, were to present itself [admittedly a non zero possibility] it would certainly raise many more questions then answered.
Religions of course would have a field day and flourish with seemingly such support for us being "special".
It does make one concerned though, that given some folk do support the concept of us being alone, that they still go about destroying and limiting our survival on this planet.
And how long before we possibily become extinct?
It would seem that if that non zero chance were true, we should have a moral obligation to protect what we do have, and to then go forth and explore and populate the Universe of which we are speculating we are alone in.
And as Jodie's Father answered in reply to her question, Οt would certainly be an awful lot of wasted space"

Selfsim
2013-Jun-25, 10:11 PM
One thing for sure, if that very unlikely scenario of us being alone, were to present itself [admittedly a non zero possibility] it would certainly raise many more questions then answered.
...
And how long before we possibily become extinct?
It would seem that if that non zero chance were true, ..Well Bobunf has provide some rather interesting fertility statistics (http://cosmoquest.org/forum/showthread.php?97916-Why-still-there-is-no-Alien-contact&p=2139955#post2139955), which seem to suggest that the 'growth' trend is negative!

Human extinction looks to be imminent! (Ie: in the same way 'the numbers' of exoplanets in the observable universe, drives the belief in exo-life!)

Worldviews are shaped by words like 'likely', 'unlikely', 'probability' … but those terms are only being used to shape others' views .. and the physical universe doesn't listen to 'em.

Colin Robinson
2013-Jun-25, 10:54 PM
One thing for sure, if that very unlikely scenario of us being alone, were to present itself [admittedly a non zero possibility] it would certainly raise many more questions then answered.
Religions of course would have a field day and flourish with seemingly such support for us being "special".

Yes, it was strengthen the element in religion that is about specialness: the idea that a particular place can be chosen for a particular blessing.


It does make one concerned though, that given some folk do support the concept of us being alone, that they still go about destroying and limiting our survival on this planet.

I agree that's a concern. Even if Earth's blessings aren't unique, it's a concern.


And as Jodie's Father answered in reply to her question, Οt would certainly be an awful lot of wasted space"

If it seems like wasted space... maybe that would stimulate some thoughtful writing. After all, one of the 20th century's most famous poems is about a wasteland.

Selfsim
2013-Jun-25, 11:08 PM
What's all this 'wasted space' business?

Who knows how much space is needed before it becomes a 'waste'?

Waste implies there's some purpose for space's usage … and yet those critical of religious views still back the view that space can be 'wasted'?

It sounds to me like those who think space can be 'wasted' are themselves, caught in confusion .. somewhere between religion and science .. they should get it straight in their minds before being critical of one or the other!

Jens
2013-Jun-26, 12:20 AM
It would seem that if that non zero chance were true, we should have a moral obligation to protect what we do have, and to then go forth and explore and populate the Universe of which we are speculating we are alone in.


I don't see what that moral obligation comes from. Isn't it just a reflection of our natural tendency to act like our smaller cousins as they expand to take up all the "wasted space" in the Petri dish? Suppose for a moment that we have a moral obligation to unborn generations to make sure that the human race does not become extinct. And suppose then that to do that we have to prevent having children who would otherwise have been born, then what about our moral obligation to those unborn individuals who might have been born? Note that I'm not arguing that we should have any moral obligation in either of those cases. I'm just saying that it seems you will get into a moral mess if you start arguing that.

It seems to me that the universe is awesome (in the original meaning of the word) as it is, and whether there are intelligent beings to experience it is not something particularly important.

Colin Robinson
2013-Jun-26, 12:33 AM
What's all this 'wasted space' business?

It is a quote from the movie Contact.


Who knows how much space is needed before it becomes a 'waste'?

Waste implies there's some purpose for space's usage … and yet those critical of religious views still back the view that space can be 'wasted'?

The idea of waste implies the idea of purpose? Yes, in the same way that the idea of meaninglessness implies the idea of meaning.


It sounds to me like those who think space can be 'wasted' are themselves, caught in confusion .. somewhere between religion and science .. they should get it straight in their minds before being critical of one or the other!

The OP of this thread asked how world-views would be affected by a conceivable future discovery that only Earth has life on it. To answer this, isn't it relevant to consider a range of world-views, including those "somewhere between religion and science"?

It is not necessarily a matter of "being critical"...

Selfsim
2013-Jun-26, 01:59 AM
… The OP of this thread asked how world-views would be affected by a conceivable future discovery that only Earth has life on it. To answer this, isn't it relevant to consider a range of world-views, including those "somewhere between religion and science"? Sure .. just as its also relevant to consider that adopting a principle of deliberately confusing science and religion, has historically and inevitably, led to measures that are unethical (http://en.wikipedia.org/wiki/Eugenics#Ethics). (The widespread implementation of eugenics policies has led to genocide).

To argue on an ethical basis, whilst deliberately mixing science with religious beliefs, can be easily shown to lead to major inconsistencies, and largely ignores past historical (empirical) evidence.


It is not necessarily a matter of "being critical"...There has already been serious, unsupported slander relating to the integrity of Creationists in this thread.

Colin Robinson
2013-Jun-26, 03:10 AM
Sure .. just as its also relevant to consider that adopting a principle of deliberately confusing science and religion, has historically and inevitably, led to measures that are unethical (http://en.wikipedia.org/wiki/Eugenics#Ethics). (The widespread implementation of eugenics policies has led to genocide).

Well, if we discover there are no other life-forms in the universe, at least we won't have to worry about Earth committing genocide against another planet, or vice versa.

Solfe
2013-Jun-26, 03:40 AM
If you are allowed to be somewhat whimsical, there is the potential for people to find this universe devoid of life and do something crazy things like try* to time travel back and forth to make sure no one is lurking at the very beginning or the end of the universe. We are pretty certain that we can't go back in time... But if we are allowing people to know the state of the whole universe, why can't we attempt to go back in time? We would also have to check all that distorted time and space around black holes and neutron stars just to be sure no one from another epoch is hiding. And think of all of the other universe that could potentially exist.

*The terrible part of being whimsical with this concept is, tell me exactly what part of traveling back in time or to other universes doesn't look exactly like flying into a black hole/worm hole to an outside observer? Option one - Object fades away. Option two - big flash of radiation and no more object. Option three is wreckage comes flying back, but then all you know is there was an engineering issue. (Sick, I may be sick.)

Jens
2013-Jun-26, 03:51 AM
But if we are allowing people to know the state of the whole universe, why can't we attempt to go back in time?

We can even now. I just tried. It didn't work though.

ASTRO BOY
2013-Jun-26, 06:16 AM
Worldviews are shaped by words like 'likely', 'unlikely', 'probability' … but those terms are only being used to shape others' views .. and the physical universe doesn't listen to 'em.



World views are simply actually shaped by observation and experiment...science no less...observation of what we see and what we don't see, and what we can logically assume from that....
But science not ever being exact, leaves open the slight possibility of the subject of this thread.
Although most unlikely in my opinion, based on the world view shaped by the scientific observations I have spoke of.
Hence the belief in the likely existence of ETL.

Human extinction on the other hand, will be guided by humans themselves, and not really imminent as you say.

And of course most [scientist and layman alike] assumed in the existence of ETL before the first exo planet was discovered, driven of course by size, extent and numbers, plus of course the Copernican Principle.

Solfe
2013-Jun-26, 06:17 AM
We can even now. I just tried. It didn't work though.

That is kind of creepy.

I have this story in mind where aliens explain to humans that time travel is possible. They say: "Moral creatures can build time machines, but only immoral creatures can use them." They refuse to answer any more questions on the subject and the human characters are afraid. They have seen several people vanish into thin air after encountering the aliens and there is the distinct possibility that there is only one time machine in the whole universe and immoral creatures can accesses it simply by thinking about it.

Sorry for the hi-jack. I return you to your normally scheduled thread.

Selfsim
2013-Jun-26, 06:39 AM
If you are allowed to be somewhat whimsical, there is the potential for people to find this universe devoid of life and do something crazy things like try* to time travel back and forth to make sure no one is lurking at the very beginning or the end of the universe. We are pretty certain that we can't go back in time... But if we are allowing people to know the state of the whole universe, why can't we attempt to go back in time? We would also have to check all that distorted time and space around black holes and neutron stars just to be sure no one from another epoch is hiding. And think of all of the other universe that could potentially exist.

*The terrible part of being whimsical with this concept is, tell me exactly what part of traveling back in time or to other universes doesn't look exactly like flying into a black hole/worm hole to an outside observer? Option one - Object fades away. Option two - big flash of radiation and no more object. Option three is wreckage comes flying back, but then all you know is there was an engineering issue. (Sick, I may be sick.)I think you'll find the best answer to that, is that the very act of 'checking all that distorted time and space around black holes', actually destroys what it is you're setting out to check for (or observe). (A theoretical QM perspective here).

So, I don't think the idea actually gets us any further, in terms of giving us a theoretically testable means of eliminating the possibility of other life (from the 'outside' observer perspective) .. whimsicality included ..

(In other words, the OP 'postulate' still can't be legitimised in this way, ie: by 'leveraging' theoretical physics laws).

Ara Pacis
2013-Jun-26, 07:18 AM
I didn't realise my question was so 'deep'!

If life outside of the Earth was somehow shown definitely not to exist, it would among other things:

1. Bring about the demise of the Dr Who (not all episodes), Star Wars and Star Trek genre which have so influenced and entertained everyone in the world under 60, with ET science fiction becoming in people's minds not even a flight of fancy about something that never was nor ever will be.We can still have ETs and Aliens. Geneticists are already creating "alien" lifeforms in labs. They can do it in space and on other planets someday. Or with enough time, it will happen naturally on other planets once we seed them... assuming that the lack of abiogenesis is merely coincidence and not a universal rule for all eternity.


2. Spur non-extraterrestrial explanations for UFOs.Time travelers who are descended from humans might not have come from Earth in the future.


3. Spur debate between Creationists and Evolutionists as to whether the non-existence of extraterrestrial life supported their respective view, or had no impact either way.I don't think conscientious evolutionists would ever find the result of no other life in the universe to support their respective view.


4. Possibly raise humanity's self-esteem in some way, whilst unsettling others.Maybe, but thinking oneself is special doesn't make one feel better about themselves. It's possible to think one is especially bad. People might think that a creator made humans, realized his error, and stopped trying and moved on to another universe to start over fresh.

parallaxicality
2013-Jun-26, 08:03 AM
There is a paradox involved in answering this question, since the only way to do so is to travel to the remotest corners of the universe and catalogue every object in it. This would require massive resources, which would require colonization, which means that, in order to prove there is no life beyond Earth, we would, by definition, need to seed worlds beyond Earth with life. Our own, but still...

Selfsim
2013-Jun-26, 08:35 AM
If somehow it could be shown with total certitude that there is no type of any life at all anywhere in the entire universe except upon the Earth ... There is a paradox involved in answering this question, since the only way to do so is to travel to the remotest corners of the universe and catalogue every object in it. This would require massive resources, which would require colonization, which means that, in order to prove there is no life beyond Earth, we would, by definition, need to seed worlds beyond Earth with life. Our own, but still...Just to clarify this ... when you say "the only way to do so is to travel .. (etc)" .. this is your opinion, right?

Ie: you're not saying its theoretically possible in the scientific domain, right?

parallaxicality
2013-Jun-26, 08:56 AM
Not sure what you mean. Even with the technology we have, we could colonise the entire universe in a few billion years. Of course, whichever of our descendants ultimately determine the truth will be as far removed from us as we are from eukaryotic unicells, which kinda reinforces the point I initially made. By that time, life in the universe will be as varied as life on Earth, if not more so.

Colin Robinson
2013-Jun-26, 10:25 AM
Not sure what you mean. Even with the technology we have, we could colonise the entire universe in a few billion years.

There are hundreds of blllions of galaxies. To colonize the lot in a few billion years, you'd have to colonize how many galaxies each year? Not with the technology we have...


Of course, whichever of our descendants ultimately determine the truth will be as far removed from us as we are from eukaryotic unicells, which kinda reinforces the point I initially made. By that time, life in the universe will be as varied as life on Earth, if not more so.

parallaxicality
2013-Jun-26, 10:44 AM
It's just a question of exponentials. Fermi showed we could colonise the entire galaxy in 50 million years. Ten stars become a hundred, a hundred become a thousand, a thousand become a million and so on. Same with galaxies.

Selfsim
2013-Jun-26, 10:52 AM
Its basically all beside the point ... there is no test for 'no life', therefore 'no life' cannot be theoretically verified (if it exists). Ie: it is not verifiable.

We have tests for carbon based life, therefore 'life' can theoretically be verified (if it exists). Ie: it is verifiable. If life is verified, then 'no life' is falsified.

It all comes down to whether the test is theoretically possible. 'No life' tests .. aren't.

The means of execution of tests, (colonisation or whatever), doesn't enter into this.

iquestor
2013-Jun-26, 12:35 PM
Its basically all beside the point ... there is no test for 'no life', therefore 'no life' cannot be theoretically verified (if it exists). Ie: it is not verifiable.

We have tests for carbon based life, therefore 'life' can theoretically be verified (if it exists). Ie: it is verifiable. If life is verified, then 'no life' is falsified.

It all comes down to whether the test is theoretically possible. 'No life' tests .. aren't.

The means of execution of tests, (colonisation or whatever), doesn't enter into this.

Actually, many of the posts are beside the point; The OP's question isn't about testing for life. it's about human psychology.

If it were somehow proven there is no ET Life beyond Earth:

1. Would people in general care more about the planet?
2. Would less emphasis be placed on space exploration?
3. Would the Space Sci Fi genre be affected?
4. Would people commit murder less?
5. Would humanities birthrate go up, or down, or be unaffected?
6. Would policies on capital punishement be affected?

Swift
2013-Jun-26, 12:52 PM
Actually, many of the posts are beside the point; The OP's question isn't about testing for life. it's about human psychology.

I predict that if the observation put forth in the OP was found to be true (that life exists only on Earth), that the LiS forum on CQ would still continue, with endless arguements and speculation. I suspect half of the discussions would be whether discussions should be allowed to continue in the LiS forum.

I suspect for the vast majority of people on Earth, nothing at all would change.

neilzero
2013-Jun-26, 12:53 PM
Not sure what you mean. Even with the technology we have, we could colonise the entire universe in a few billion years. Of course, whichever of our descendants ultimately determine the truth
I can't imagine a scenario, where that truth could be found.
Suppose Earth built and launched a star ship annually for the next million years, each for a different destination = one million star ships. The crew of 99% died enroute. Of the 10,000 that attempted a new colony in a new star system, 99% died out = 100 new colonies which lasted long enough to start sending out star ships once per year or some lessor rate. With today's technology those are very optimistic results, which produce about 100 long lasting colonies per million years, so our galaxy would be only partially colonized in a million times a million years. Other galaxies would remain beyond probable reach even with modest technical advances except when they merged with our galaxy which will happen occasionally in a million times a million years.
The truth remains elusive, as no messages from a far away colony neither proves nor disprove that they are alive nor all dead. Neil

Solfe
2013-Jun-26, 01:09 PM
(A theoretical QM perspective here).


Actually, I was thinking deep, but not QM deep. The aliens would be hiding outside a black hole or neutron star using it like a "fast forward" machine instead of looking for us, they merely hide and wait. Something like all the aliens in Brin's Crystal Sphere or Reynold's Revelation Space novels.

swampyankee
2013-Jun-26, 01:41 PM
I predict that if the observation put forth in the OP was found to be true (that life exists only on Earth), that the LiS forum on CQ would still continue, with endless arguements and speculation. I suspect half of the discussions would be whether discussions should be allowed to continue in the LiS forum.

I suspect for the vast majority of people on Earth, nothing at all would change.

I would thing both sentences are correct.

One of the posters said this entire discussion is stupid; I disagree, as this is a testable hypothesis:

first, determine, by standard sociological methods, what current beliefs are. If nobody believes (or cares) about life beyond Earth, demonstrating that it is extremely unlikely to exist (we've got one data point. It is equally logical to assume that life, even intelligent life, is very common as to assume it's rare or unique) is unlikely to have major sociological effects.

second, show, by sufficient testing that life does not exist beyond Earth (we can't do that now, but we can't test string theory, either)

third, repeat step 1.

fourth, evaluate the changes between steps 1 and 3. I'd expect these to remain small because, as you said, most people simply don't care.

eburacum45
2013-Jun-26, 04:40 PM
second, show, by sufficient testing that life does not exist beyond Earth (we can't do that now, but we can't test string theory, either)


This is an impossible step, as far as I can see. We cannot ever reach a large portion of the galaxies that are visible in the Hubble Deep Field (or at comparable distances), because of the expansion of the Universe. Yet we know those galaxies exist, (or existed), because we can see them.

That means we can never prove that life does not exist beyond Earth.

kzb
2013-Jun-26, 05:39 PM
This is an impossible step, as far as I can see. We cannot ever reach a large portion of the galaxies that are visible in the Hubble Deep Field (or at comparable distances), because of the expansion of the Universe. Yet we know those galaxies exist, (or existed), because we can see them.

That means we can never prove that life does not exist beyond Earth.

I agree, it can't ever be proven beyond doubt. But as a thought experiment I can go along with the question. What it would prove is that abiogenesis is indeed extremely unlikely, as some still hypothesize.

Personally I don't see why it should be a "punch to the gut" as someone says previously. In some ways it is a disappointment, but in other ways it's an advantage.

No strange SF creatures to study, but equally no super-advanced races to out-compete us. The whole universe within our horizon is theoretically available for us to use at will.

Paul Wally
2013-Jun-26, 07:04 PM
Actually, I was thinking deep, but not QM deep. The aliens would be hiding outside a black hole or neutron star using it like a "fast forward" machine instead of looking for us, they merely hide and wait. Something like all the aliens in Brin's Crystal Sphere or Reynold's Revelation Space novels.

Actually they don't necessarily need to hide. They just have to exist outside of our light cone (http://en.wikipedia.org/wiki/Light_cone).

ASTRO BOY
2013-Jun-26, 08:06 PM
There is a paradox involved in answering this question, since the only way to do so is to travel to the remotest corners of the universe and catalogue every object in it. This would require massive resources, which would require colonization, which means that, in order to prove there is no life beyond Earth, we would, by definition, need to seed worlds beyond Earth with life. Our own, but still...





Put simply the near infinite state of the Universe [if not infinite] and the near infinite numbers involved, make "proof" that we are alone impossible to derive or even contemplate, while at the same time enforcing the more reasonable proposal that it does exist somewhere sometime.
Which is why the hypothetical question at hand, would be a real game changer in many respects [as I have mentioned earlier] if it were shown to be true.

ASTRO BOY
2013-Jun-26, 08:07 PM
Actually they don't necessarily need to hide. They just have to exist outside of our light cone (http://en.wikipedia.org/wiki/Light_cone).

Bingo!

Githyanki
2013-Jun-27, 12:09 AM
By the time humanity is certain Earth was the only place where life developed in the galaxy, it could be millions of years in the future and humanity could be something totally different or have no idea that life was from Earth.

It doesn't really matter if life only came from Earth; if humanity can travel through space, over time, life will be everywhere in the galaxy.

Perhaps "Life" already did, 4BYA ago and life is everywhere by now.

Ara Pacis
2013-Jun-27, 01:18 AM
Put simply the near infinite state of the Universe [if not infinite] and the near infinite numbers involved, make "proof" that we are alone impossible to derive or even contemplate, while at the same time enforcing the more reasonable proposal that it does exist somewhere sometime.
Which is why the hypothetical question at hand, would be a real game changer in many respects [as I have mentioned earlier] if it were shown to be true.

Nope. It can be contemplated. And it does not make it more reasonable to enforce a proposal that the opposite is true or likely.

We cannot currently travel beyond our light cone with known science, but the OP does not rule out scientific possibilities yet to be discovered or technical challenges that might be worked around. But even accepting that we may never see what's outside our light cone, the existence of that unknown does not increase the probability or the logical argument that life could exist in that space. We wouldn't even be able to know if planets exist for life to live on in the area beyond our lightcone.

Moreover, Parsimony still bites proponents of life in the butt even if we consider a limitation of the lightcone in place of the certitude in the OP's thought experiment. After all, which is more likely when we consider the evidence that there is no other life inside our lightcone: that there is no other life in the universe, or that life can happen but the circumstances for it are so rare that it only occurred once in our lightcone?

As for "proof" that we are alone, we do have that evidence. It's just not empirical.

ASTRO BOY
2013-Jun-27, 02:17 AM
Nope. It can be contemplated. And it does not make it more reasonable to enforce a proposal that the opposite is true or likely..


Respectfully it is far more reasonable to propose ETL then not to....for the reasons stated. Really we are not that special.











We cannot currently travel beyond our light cone with known science, but the OP does not rule out scientific possibilities yet to be discovered or technical challenges that might be worked around. But even accepting that we may never see what's outside our light cone, the existence of that unknown does not increase the probability or the logical argument that life could exist in that space. We wouldn't even be able to know if planets exist for life to live on in the area beyond our lightcone..






Disagree again. We can logically assume as we do with the Isotropic and hemogenous aspects of the observable Universe. No reason why beyond that bubble would be any different.





Moreover, Parsimony still bites proponents of life in the butt even if we consider a limitation of the lightcone in place of the certitude in the OP's thought experiment. After all, which is more likely when we consider the evidence that there is no other life inside our lightcone: that there is no other life in the universe, or that life can happen but the circumstances for it are so rare that it only occurred once in our lightcone?.





Parsimony does nothing of the sort when we look at it logically, especially with regards to time and distance between events and Aliens.
And of course we have no evidence whatsoever that we are alone within our own light cone let alone the Universe as a whole.
But for the sake of argument lets be parsimonious and say ETI exists one time per galaxy....Now how many galaxies do we have?







As for "proof" that we are alone, we do have that evidence. It's just not empirical.



Considering that we have barely left Earth's cradle to explore what is out there, that just does not hold water.
But in any event, this thread is about the unlikely hypothesis or "thought experiment"concerning cultural shock if we were alone.
Like I said up there, I would crawl back to the Catholic church and ask for my excommunnication to be revoked.

Ara Pacis
2013-Jun-27, 04:15 AM
Why so much line spacing? Seriously, that's weird.


Respectfully it is far more reasonable to propose ETL then not to....for the reasons stated. Really we are not that special. Nope. According the the constraints of the OP's thought experiment, we would be that special.


Disagree again. We can logically assume as we do with the Isotropic and hemogenous aspects of the observable Universe. No reason why beyond that bubble would be any different.Are you suggesting that if the ratio of life that we would have observed in our lightcone is trillions upon trillions of places devoid of life and exactly 1 place that has life, that there might be a population of exactly 1 planet with life in the next lightcone over?


Parsimony does nothing of the sort when we look at it logically, especially with regards to time and distance between events and Aliens.You did not explain this. How does a conclusion from the constraints of the OP (and lightcone limitation addendum), that arrives at devoid of life contain more assumptions than the conclusion that there's life, but it's hiding in the shadows just beyond the photons of yesterday?


But for the sake of argument lets be parsimonious and say ETI exists one time per galaxy....Now how many galaxies do we have?the OP and my response posit the entirety of the universe, although some have argued the lightcone for sake of theoretical empiricism, however, further regression to mere galaxies would constitute a altogether different level of change in the argument rendering it a strawman.


Considering that we have barely left Earth's cradle to explore what is out there, that just does not hold water.
But in any event, this thread is about the unlikely hypothesis or "thought experiment"concerning cultural shock if we were alone.
Like I said up there, I would crawl back to the Catholic church and ask for my excommunnication to be revoked.I was referring to religion, as my earlier post stated. What does the amount of space exploration have to do with the veracity of falsity of non-empirical proclamations of proof that humans are alone in the universe?

ASTRO BOY
2013-Jun-27, 09:39 AM
Why so much line spacing? Seriously, that's weird.




Not from where I stand/sit.....







Nope. According the the constraints of the OP's thought experiment, we would be that special..





I was comparing the hypothesis of the OP being highly speculative as opposed to reasonable scientific speculation of the presence of ETL and the unlikelyhood of that "special"quality.
But yes, obviously it goes without saying that within the constraints of the OP we would be special.







Are you suggesting that if the ratio of life that we would have observed in our lightcone is trillions upon trillions of places devoid of life and exactly 1 place that has life, that there might be a population of exactly 1 planet with life in the next lightcone over?

You did not explain this. How does a conclusion from the constraints of the OP (and lightcone limitation addendum), that arrives at devoid of life contain more assumptions than the conclusion that there's life, but it's hiding in the shadows just beyond the photons of yesterday?

the OP and my response posit the entirety of the universe, although some have argued the lightcone for sake of theoretical empiricism, however, further regression to mere galaxies would constitute a altogether different level of change in the argument rendering it a strawman.

I was referring to religion, as my earlier post stated. What does the amount of space exploration have to do with the veracity of falsity of non-empirical proclamations of proof that humans are alone in the universe?
.[/QUOTE]




Off track as I have mentioned earlier.
Perhaps we could continue in another of the threads based on the overwhelming possibility of ETL as opposed to the unreasonable alternative as asked for in the OP.

We do agree on one point I see....that religions would have plenty of reasons to flourish.
Now that would be a drawback for science!

parallaxicality
2013-Jun-27, 10:12 AM
I don't see the point of this speculation: us being alone in the universe is, for all intents and purposes, the ground state by which the human race operates. Finding absolute proof of that would change nothing whatsoever, particularly given how little most people are interested in science in the first place.

profloater
2013-Jun-27, 10:14 AM
I don't see the point either, but it takes all sorts to make a life form forum I guess.

iquestor
2013-Jun-27, 11:48 AM
I don't see the point of this speculation: us being alone in the universe is, for all intents and purposes, the ground state by which the human race operates. Finding absolute proof of that would change nothing whatsoever, particularly given how little most people are interested in science in the first place.

I dont agree, and neither does the general public.

1. Half of Americans believe in ET (http://www.huffingtonpost.com/2013/06/21/alien-poll_n_3473852.html)
2. Belief in ET is a Growing Trend (http://www.alienresistance.org/ufo-alien-deception/recent-polls-trends-belief-aliens-ufos/)
3. Poll: Do you beleive in Alien Life? (http://www.blogpoll.com/poll/act_Vote.php)

- The US and other countries have spent billions looking for existance of ET Life, and there is a profound interest in finding it.
- The last 3 Mars rovers explicitly are searching for environments where life could have formed.
- SETI has been going on since the 70s, looking for ETI.

So, how do you support your statement above? perhaps you meant that whether there is or isnt ET life is not a major impact on our daily lives.
I would agree with that, until its proven one way, or the other. Then it will have an impact on many of the population, but not all.

parallaxicality
2013-Jun-27, 01:40 PM
They may believe (for a given value of "believe"), but does that belief affect how they view themselves or their place in the world? Half of Americans also believe that the world is 6000 years old or less, and thus that human beings are held in a certain special regard by a deity. Finding out we are alone in the universe will do little to change that.

iquestor
2013-Jun-27, 04:54 PM
They may believe (for a given value of "believe"), but does that belief affect how they view themselves or their place in the world? Half of Americans also believe that the world is 6000 years old or less, and thus that human beings are held in a certain special regard by a deity. Finding out we are alone in the universe will do little to change that.

I feel that you are making up statistics. I very very seriously doubt HALF of the US population thinks the Earth is 6000 years Old. Where did you get that idea?
maybe you meant half of christians in america?

What does a "deity holding us in special regard" have to do with anything? I dont know any religious people who think that their religious beliefs exclude the Earth being 4 billion years old.

parallaxicality
2013-Jun-27, 05:11 PM
Here. (http://www.gallup.com/poll/155003/Hold-Creationist-View-Human-Origins.aspx)

Anyone who believes that the world is less than 10,000 years old would also need to believe in the covenant between God and man, otherwise, why would you go to the trouble?

iquestor
2013-Jun-27, 05:43 PM
Here. (http://www.gallup.com/poll/155003/Hold-Creationist-View-Human-Origins.aspx)

Anyone who believes that the world is less than 10,000 years old would also need to believe in the covenant between God and man, otherwise, why would you go to the trouble?


that link doesn't support your statement. (bold , mine)

Half of Americans also believe that the world is 6000 years old or less

it says those people believe HUMANS were created in the last 10K years by an intelligent Deity.

I agree that those who beleive the earth is thousands of years old rather than billions are overwhelmingly religious.

swampyankee
2013-Jun-27, 11:47 PM
There's a large number of people on Earth (and quite a few in, say, the US) who don't have a good idea of whether they're going to get a next meal; these people are not likely to be too concerned about a lack of ETs. There will also, doubtlessly and unfortunately, going to be some whose main feeling is one of regret that there are no aliens to conquer, subjugate, enslave, or exterminate.

Me? I'd be surprised. Of course, by the time we could discuss the presence or absence of aliens without speculation, I'm likely to have been recycled or fossilized.

Ara Pacis
2013-Jun-29, 05:50 PM
Not from where I stand/sit.....Why you gotta be argumentative about everything, or are you visually-impaired and need extra space for a special reader?


I was comparing the hypothesis of the OP being highly speculative as opposed to reasonable scientific speculation of the presence of ETL and the unlikelyhood of that "special"quality.It wasn't a hypothesis and it wasn't speculative. Hypotheses and speculations/conjectures are attempts to explain observations. The OP was not attempting to explain an observation. There was no observation mentioned and the OP posed a question, not an answer. The thought experiment might be thought of as a hypothetical, but a hypothetical is not the same thing as a hypothesis, especially in this usage where the thing that everyone is arguing about is the Proposition instead of the consequent, for the proposition cannot be at issue because it stands by fiat.


But yes, obviously it goes without saying that within the constraints of the OP we would be special.Yup. Thanks for understanding.


Off track as I have mentioned earlier.Yup. I agree, the lightcone aspect is immaterial, if we somehow know the answer is negative for trillions of locations near us, then we would be confronted with an overwhelming possibility that ETL does not exist.


Perhaps we could continue in another of the threads based on the overwhelming possibility of ETL as opposed to the unreasonable alternative as asked for in the OP. What would be the point? You've already shown your propensity to ignore math and logic on that issue in previous threads.


We do agree on one point I see....that religions would have plenty of reasons to flourish.
Now that would be a drawback for science!Maybe. Certainly it would be bad for SETI type science. I'm not sure how it would impact any other science, unless you're saying that people would give up their iPads to join Lonely-Earth cults to quell some fear or cognitive dissonance from learning that we are alone. I'd as easily expect some religions to start saying that it's our duty to spread life through the universe and cause a jump in space-related science spending

Ara Pacis
2013-Jun-29, 05:57 PM
I don't see the point of this speculation: us being alone in the universe is, for all intents and purposes, the ground state by which the human race operates. Finding absolute proof of that would change nothing whatsoever, particularly given how little most people are interested in science in the first place.

The point of the question in the OP is to stir up a hornets nest, obviously.

Paul Beardsley
2013-Jun-29, 06:01 PM
What would be the point? You've already shown your propensity to ignore math and logic on that issue in previous threads.

Seconded.

ASTRO BOY
2013-Jun-29, 08:02 PM
Why you gotta be argumentative about everything, or are you visually-impaired and need extra space for a special reader?






I'm not .....If you object to my style, I'm sorry...*shrug*

The rest of your post is just supposition and opinionated.

ASTRO BOY
2013-Jun-29, 10:22 PM
I dont agree, and neither does the general public.

1. Half of Americans believe in ET (http://www.huffingtonpost.com/2013/06/21/alien-poll_n_3473852.html)
2. Belief in ET is a Growing Trend (http://www.alienresistance.org/ufo-alien-deception/recent-polls-trends-belief-aliens-ufos/)
3. Poll: Do you beleive in Alien Life? (http://www.blogpoll.com/poll/act_Vote.php)

- The US and other countries have spent billions looking for existance of ET Life, and there is a profound interest in finding it.
- The last 3 Mars rovers explicitly are searching for environments where life could have formed.
- SETI has been going on since the 70s, looking for ETI.

So, how do you support your statement above? perhaps you meant that whether there is or isnt ET life is not a major impact on our daily lives.
I would agree with that, until its proven one way, or the other. Then it will have an impact on many of the population, but not all.



That pretty well hits the nail on the head.
I would add again though, that in that very unlikely scenario it was shown we were alone, religions would have a field day in relation to Earth being special.

Selfsim
2013-Jun-29, 11:01 PM
I dont agree, and neither does the general public.

1. Half of Americans believe in ET (http://www.huffingtonpost.com/2013/06/21/alien-poll_n_3473852.html)
2. Belief in ET is a Growing Trend (http://www.alienresistance.org/ufo-alien-deception/recent-polls-trends-belief-aliens-ufos/)
3. Poll: Do you beleive in Alien Life? (http://www.blogpoll.com/poll/act_Vote.php)

- The US and other countries have spent billions looking for existance of ET Life, and there is a profound interest in finding it.
- The last 3 Mars rovers explicitly are searching for environments where life could have formed.
- SETI has been going on since the 70s, looking for ETI.

So, how do you support your statement above? perhaps you meant that whether there is or isnt ET life is not a major impact on our daily lives.
I would agree with that, until its proven one way, or the other. Then it will have an impact on many of the population, but not all.This is part of a superficial perception, eagerly being propagated in order to secure public support.

Exploring the universe tells us things about ourselves. Finding an ET, would tell us even more about ourselves, but there are other ways to do this. I think the folk included in the above surveys would spend most of their days getting to know about themselves. Knowledge of ET, wouldn't even register on their radars, unless it was put right under their noses … (like by being deliberately confronted by enthusiasts' survey questions, demanding their opinions on ETs).

ASTRO BOY
2013-Jun-29, 11:40 PM
So perhaps the OP's question could be reworked in a less fantastic form:

If it could be shown as highly improbable that there is any type of any life at all anywhere in the entire universe except upon the Earth, how would this change the average astronomer's/cosmologist's/person's worldview, if at all?



I agree that makes far more sense, although still rather hard to over turn the present assumption that ETL somewhere, somettime is highly probable.
We would still logically be containing ourselves to the observable Universe and the present time.

Ara Pacis
2013-Jun-30, 06:31 AM
I'm not .....If you object to my style, I'm sorry...*shrug*

The rest of your post is just supposition and opinionated.

Brave, Brave sir Robin.

iquestor
2013-Jul-01, 01:07 PM
This is part of a superficial perception, eagerly being propagated in order to secure public support.

Exploring the universe tells us things about ourselves. Finding an ET, would tell us even more about ourselves, but there are other ways to do this. I think the folk included in the above surveys would spend most of their days getting to know about themselves. Knowledge of ET, wouldn't even register on their radars, unless it was put right under their noses … (like by being deliberately confronted by enthusiasts' survey questions, demanding their opinions on ETs).

Really? the old "All those people are <idiots/misguided/biased/prejudiced/stupid/brainwashed/assimilated/narrowminded/...> so the results don't count" argument. Right.

TheyDidGoToTheMoon
2013-Jul-01, 01:31 PM
Mars' surface looks quite Earth-like, apart for its utter lifelessness.

If somehow it could be shown with total certitude that there is no type of any life at all anywhere in the entire universe except upon the Earth, apart from deflating some ufologists and Star Trek buffs and rediverting some SETI budgets, how would this change the average astronomer's/cosmologist's/person's worldview, if at all?

This is an impossible question, because the galaxy and universe need to be explored first, such as Curiosity on Mars is our first step and may be only step...:rolleyes:

MaDeR
2013-Jul-01, 04:21 PM
We cannot reach the conclusion that "life should be a normal by-product of the universe functioning". We only have 1 example.
Two decades ago: We cannot reach the conclusion that "planets should be a normal by-product of the universe functioning". We only have 1 example [of planets around star].
Nope, you are not convincing at all.

In my opinion, our knowledge about universe is already enough to assess and indicate that life should be a normal by-product of laws of the universe.


For example, would the community then turn, and look at Carl Sagan as being someone who perpetrated a massive deception, using science as the means? (Sagan being the Grand-Dad of SETI, that is).
Now that is one hilarious accussation.

There has already been serious, unsupported slander relating to the integrity of Creationists in this thread.
Feel free to talk more, I for once feel you have way, way more opinions about various things than you let in on this forum (and for good reason).

iquestor
2013-Jul-01, 06:33 PM
Two decades ago: We cannot reach the conclusion that "planets should be a normal by-product of the universe functioning". We only have 1 example [of planets around star].
Nope, you are not convincing at all.

In my opinion, our knowledge about universe is already enough to assess and indicate that life should be a normal by-product of laws of the universe.



the statement in the quote above was absolutely correct UNTIL we received information that planets were common. prior to that, no one could say if they were, or were not.

Your opinion is based on faulty logic. And Facts don't have to be convincing. they are facts. It is a fact that There is exactly 1 known planet in the universe that we know of that has life. We cannot use that 1 instance to prove or even argue that life is common or rare or unique. Find another planet with life, and I will agree with you that life is very probably common.

Paul Beardsley
2013-Jul-01, 06:46 PM
the statement in the quote above was absolutely correct UNTIL we received information that planets were common. prior to that, no one could say if they were, or were not.

Your opinion is based on faulty logic. And Facts don't have to be convincing. they are facts. It is a fact that There is exactly 1 known planet in the universe that we know of that has life. We cannot use that 1 instance to prove or even argue that life is common or rare or unique. Find another planet with life, and I will agree with you that life is very probably common.

Exactly right.

Look, guys, this is a science board. Can we please be scientific. I want to know there is ET life out there as much as anyone else, possibly more so, but I am prepared to wait until there is enough evidence to make meaningful statements, and I think others should be too.

Swift
2013-Jul-01, 07:34 PM
Exactly right.

Look, guys, this is a science board. Can we please be scientific. I want to know there is ET life out there as much as anyone else, possibly more so, but I am prepared to wait until there is enough evidence to make meaningful statements, and I think others should be too.
I'm going to to quote Paul's post, but this is aimed broadly.

Quite frankly, I would not even call the topic of the OP "speculative", or even "science fiction"... more like fantasy. I understand your concern about scientifically accurate statements, but given the nature of this thread, I don't see any problem with wild speculation. Let's just keep it out of the less speculative threads.

ASTRO BOY
2013-Jul-01, 08:42 PM
In my opinion, our knowledge about universe is already enough to assess and indicate that life should be a normal by-product of laws of the universe.
.








I know another great bloke that posts here and agrees with that summation 100%!








Now that is one hilarious accussation..








I have made reference somewhere about individuals rubbishing and poo pooing science presenters including Sagan....Maybe they need to take up the cudgel themselves and do try and do better.







Feel free to talk more, I for once feel you have way, way more opinions about various things than you let in on this forum (and for good reason).





The TV science presenters that I am familiar with, all assume that ETL is far more likely then not, including the great Carl Sagan.
Could this be a bearing for some of the criticism of these science presenters?

Swift
2013-Jul-01, 09:54 PM
I know another great bloke that posts here and agrees with that summation 100%!

I have made reference somewhere about individuals rubbishing and poo pooing science presenters including Sagan....Maybe they need to take up the cudgel themselves and do try and do better.

The TV science presenters that I am familiar with, all assume that ETL is far more likely then not, including the great Carl Sagan.
Could this be a bearing for some of the criticism of these science presenters?
ASTRO BOY,

I'm quoting your post, but this may apply to others - please stick to the topic of the thread. I have not idea where exactly you are going, but we don't need yet another thread about science presenters or the likelihood of ETLs. The OP presents a very specific assumption - let's stick to that.

ASTRO BOY
2013-Jul-01, 10:37 PM
No problems.

swampyankee
2013-Jul-01, 10:44 PM
As for "proof" that we are alone, we do have that evidence. It's just not empirical.

If it's not empirical (http://www.merriam-webster.com/dictionary/empirical), it's not evidence; it's supposition. I don't have anything against supposition or speculation as long as it's not claimed to be evidence.

Jens
2013-Jul-01, 11:21 PM
This is an impossible question, because the galaxy and universe need to be explored first, such as Curiosity on Mars is our first step and may be only step...:rolleyes:

This has been stated already, but I do think it's possible. One possibility is that we discover we live in a simulation, and everything outside our planet is just props.

Selfsim
2013-Jul-01, 11:44 PM
Now that is one hilarious accussation.'Twas a speculative question, there MaDer .. not an accusation. But hey, we're in a thread which permits unbridled speculation for entertainment value aren't we? (That's how it started out, eh?).


Feel free to talk more, I for once feel you have way, way more opinions about various things than you let in on this forum (and for good reason).Why thanks, MaDer! :) I think you really need to look more closely into where I'm coming from .. opinions don't really make a difference in some topics anyway, eh?

PS:
Aside: Where were you when I did my thread on the 'Copernican Fallacy & Numbers' (http://cosmoquest.org/forum/showthread.php?140478-Copernican-Fallacy-amp-Numbers)? (I was really hoping you'd drop in on it)

Ara Pacis
2013-Jul-02, 06:05 AM
If it's not empirical (http://www.merriam-webster.com/dictionary/empirical), it's not evidence; it's supposition. I don't have anything against supposition or speculation as long as it's not claimed to be evidence.

Nope.

And how does linking to a definition of empirical help make your argument about evidence? They are not synonyms.

MaDeR
2013-Jul-04, 10:05 PM
the statement in the quote above was absolutely correct UNTIL we received information that planets were common. prior to that, no one could say if they were, or were not.
Wrong. When we knew only about planets around our sun, we could and did developed models of solar system creation. These models indicated that planets should form around other stars. We could conclude that "planets should be a normal by-product of solar system formation" (implying they are common). This hypothesis was confirmed later.

Now we have this all over again, only with life instead. Current hypothesis (and my claim) is "our knowledge about universe, laws of physics etc indicate life should be normal byproduct of laws of this universe".

Before you say anything, no, I did not claim that existence of extraterrestial life was proven or something like that. I said that life outside Earth should exist. In other words, I consider extraterrestial life as very probable. I dont know how I can get any more clear than this.


'Twas a speculative question, there MaDer .. not an accusation.
Let me rephrase, then. Accusation masked as "just asking".


Aside: Where were you when I did my thread on the 'Copernican Fallacy & Numbers' (http://cosmoquest.org/forum/showthread.php?140478-Copernican-Fallacy-amp-Numbers)? (I was really hoping you'd drop in on it)
Some old thread that I never participated in? Why I would care? Don't tell me I have some obligation to write posts and responses in each and every thread that you made.

Selfsim
2013-Jul-04, 11:33 PM
For example, would the community then turn, and look at Carl Sagan as being someone who perpetrated a massive deception, using science as the means? (Sagan being the Grand-Dad of SETI, that is).Let me rephrase, then. Accusation masked as "just asking".Nope. Its an enquiry into what a general group (public) response might be, if through misunderstanding of what pursuit of a real scientific hypothesis is, (which is what Sagan initiated), it is decided that the hunt for ETIs is indistinguishable from pseudoscience. Would the general group (public) then develop a perception that it was deceived, which it then might hold against its initiator?
There is lots of evidence for this kind of retaliation .. like the recent Italian court-case against scientists re: Earthquake risk prediction, and the perception flowing from the ambiguous Viking Life tests .. (just to name a couple).

Remember my initial comments on this (post #55 (http://cosmoquest.org/forum/showthread.php?144844-If-life-was-shown-to-exist-only-on-Earth&p=2140794#post2140794)):
Sagan was certainly known for his 'popularization' of science and for his efforts to increase scientific understanding among the general public. He took positions in favor of scientific skepticism and against pseudoscience … and yet, the search for aliens is very much dominated by a hypothesis which asserts the possibility of their existence to be true.
...

Some old thread that I never participated in? Why I would care? Don't tell me I have some obligation to write posts and responses in each and every thread that you made.No .. not at all … but your rigid stance, (from past conversations with you), that the Copernican Principle necessarily realises the existence of exo-life, is based on logical fallacy, which is what motivated that thread. You raised the same argument, (if I'm not mistaken), in your response to your post #124).

swampyankee
2013-Jul-05, 02:43 AM
Nope.

And how does linking to a definition of empirical help make your argument about evidence? They are not synonyms.

In your post (http://cosmoquest.org/forum/showthread.php?144844-If-life-was-shown-to-exist-only-on-Earth&p=2141204#post2141204) you stated "As for 'proof' that we are alone, we do have that evidence. It's just not empirical." My statement was that evidence can only be empirical; the link to the definition was so that somebody would not pipe up and say that observation, not just experiment, can provide evidence. I will concede that there is no current evidence that humanity is not alone; there was, until fairly recently, no evidence that the Higgs boson existed; that it was theoretically predicted within the Standard Model did not provide evidence for its existence.

Ara Pacis
2013-Jul-05, 03:38 AM
In your post (http://cosmoquest.org/forum/showthread.php?144844-If-life-was-shown-to-exist-only-on-Earth&p=2141204#post2141204) you stated "As for 'proof' that we are alone, we do have that evidence. It's just not empirical." My statement was that evidence can only be empirical; the link to the definition was so that somebody would not pipe up and say that observation, not just experiment, can provide evidence. I will concede that there is no current evidence that humanity is not alone; there was, until fairly recently, no evidence that the Higgs boson existed; that it was theoretically predicted within the Standard Model did not provide evidence for its existence.

Yeah, no. Religious claims of revelation of information can be evidence, by they are not empirical.

Selfsim
2013-Jul-05, 04:44 AM
Wrong. When we knew only about planets around our sun, we could and did developed models of solar system creation. These models indicated that planets should form around other stars. We could conclude that "planets should be a normal by-product of solar system formation" (implying they are common). This hypothesis was confirmed later.

Now we have this all over again, only with life instead. Current hypothesis (and my claim) is "our knowledge about universe, laws of physics etc indicate life should be normal byproduct of laws of this universe".

Before you say anything, no, I did not claim that existence of extraterrestial life was proven or something like that. I said that life outside Earth should exist. In other words, I consider extraterrestial life as very probable. I dont know how I can get any more clear than this.There were direct, explicit relationships describing the universal laws of motion, and the universal laws of gravitation and matter, which was known to be applicable for describing what happens to matter and gas in space. Firm physical predictions about the formation of planets could therefore be made from models based on these laws.

There are no equivalent laws describing the processes which result in the elements and inorganic compounds coming together to form life. Firm predictions from science, thus cannot be made about its formation. Tentative, speculative predictions about non-terrestrial life, must treat the existence of life phenomenologically, and seek out evidence elsewhere, in order for the idea to be extracted from the realm of speculation.

There's a big difference between the two scenarios, which you cite as being analogously equivalent, (and use to assert others being 'wrong'). Having an opinion about it was fine .. but it seems your opinion has now shifted to declaring others to be 'wrong' about theirs(?)

Consider: there is no physical law, which explains why there has only ever been one unique MaDer (as far as we know).

ASTRO BOY
2013-Jul-05, 09:05 PM
Wrong. When we knew only about planets around our sun, we could and did developed models of solar system creation. These models indicated that planets should form around other stars. We could conclude that "planets should be a normal by-product of solar system formation" (implying they are common). This hypothesis was confirmed later.

Now we have this all over again, only with life instead. Current hypothesis (and my claim) is "our knowledge about universe, laws of physics etc indicate life should be normal byproduct of laws of this universe".

Before you say anything, no, I did not claim that existence of extraterrestial life was proven or something like that. I said that life outside Earth should exist. In other words, I consider extraterrestial life as very probable. I dont know how I can get any more clear than this.







That overwhelmingly appears to be the position of most if not all reputable scientists for obvious reasons, which makes the speculative scenario of the OP very very unlikely.
And is the reason that in my opinion if that unlikely situation were true [that is we were alone] it would be a boost for religion and the existence of a deity, intelligent design, and us, and Earth really being special, taking us back to the Ptolomec era.

Ara Pacis
2013-Jul-05, 11:24 PM
That overwhelmingly appears to be the position of most if not all reputable scientists for obvious reasons, which makes the speculative scenario of the OP very very unlikely.
And is the reason that in my opinion if that unlikely situation were true [that is we were alone] it would be a boost for religion and the existence of a deity, intelligent design, and us, and Earth really being special, taking us back to the Ptolomec era.

I really don't think it would undo our understanding of gravitation and that planets, moons and other objects don't all orbit Earth.

ASTRO BOY
2013-Jul-06, 01:10 AM
I really don't think it would undo our understanding of gravitation and that planets, moons and other objects don't all orbit Earth.



Probably correct....I was speaking primarily of the Intelligent design, existence of a deity and probably afterlife caper flourishing.

KABOOM
2013-Jul-06, 01:02 PM
That overwhelmingly appears to be the position of most if not all reputable scientists for obvious reasons, which makes the speculative scenario of the OP very very unlikely.
And is the reason that in my opinion if that unlikely situation were true [that is we were alone] it would be a boost for religion and the existence of a deity, intelligent design, and us, and Earth really being special, taking us back to the Ptolomec era.

I do strongly concur with this viewpoint, recognizing fully that this premise is limited to that of a "thought experiment". If you couple the fact that 1) despite all our scientific advances we can not replicate abiogenesis or demonstrate as to how it occurred and 2) if it could (it can't) be proven that life in the universe is limited to Earth this would provide tremendous lift to the deity/ID crowd and understandably so. For the expanses of universal space and the pages on the universal calendar to date are so incomprehensibly vast, that if we on our lonely blue dot are truly "it" the question of "why" becomes incredibly profound.

Jens
2013-Jul-08, 01:01 AM
And is the reason that in my opinion if that unlikely situation were true [that is we were alone] it would be a boost for religion and the existence of a deity, intelligent design, and us, and Earth really being special, taking us back to the Ptolomec era.

I'm not sure exactly what you mean by the "Ptolemaic era," though I suppose you mean believing the earth is the center of everything. As a response to the OP, I don't really think that it would change much. For one thing, believing in a deity doesn't prevent one from conducting scientific inquiry. Just as an example, my own favorite religious figure, Pythagoras, was apparently a believer in a creator, but saw the study of mathematics in particular as a way to understand the creator, and so he was (I think) quite scientifically minded in a way. So personally, it wouldn't really change my outlook much. I would still be interested in science fiction, in the same way that I enjoyed Harry Potter even though I'm quite aware that dragons and magic spells don't really exist. It would probably decrease my interest in SETI ventures though!

ASTRO BOY
2013-Jul-08, 02:41 AM
I'm not sure exactly what you mean by the "Ptolemaic era," though I suppose you mean believing the earth is the center of everything. As a response to the OP, I don't really think that it would change much. For one thing, believing in a deity doesn't prevent one from conducting scientific inquiry. Just as an example, my own favorite religious figure, Pythagoras, was apparently a believer in a creator, but saw the study of mathematics in particular as a way to understand the creator, and so he was (I think) quite scientifically minded in a way. So personally, it wouldn't really change my outlook much. I would still be interested in science fiction, in the same way that I enjoyed Harry Potter even though I'm quite aware that dragons and magic spells don't really exist. It would probably decrease my interest in SETI ventures though!



Personally I wouldn't change much either, although I was caught being fecetious early on in the piece, re getting my excommunication from the Catholic church reviewed.

Also you need not go back to Pythagoras, George Le-Mataire will suffice, a Jesuit Priest no less.
Yes, and obviously interest in SETI would wane somewhat.
I do think though generally speaking, that the church would have a great flock of "born again Christains ready to baptise.

And as long as cosmology has no answers to the whys and hows of the BB, those so inclined will always put it down to the work of God.

MaDeR
2013-Jul-10, 05:53 PM
Nope. Its an enquiry into what a general group (public) response might be, if through misunderstanding of what pursuit of a real scientific hypothesis is, (which is what Sagan initiated), it is decided that the hunt for ETIs is indistinguishable from pseudoscience.
Who would decide that and on what basis?


Would the general group (public) then develop a perception that it was deceived, which it then might hold against its initiator?
Probably. Witch hunts are popular pasttime.


There are no equivalent laws describing the processes which result in the elements and inorganic compounds coming together to form life.
Despite your claims, we know thing or two about life. While abiogenesis is indeed very murky, your sentences comes dangerously close to claiming that abiogenesis is impossible according to known laws of physics.


but your rigid stance, that the Copernican Principle necessarily realises the existence of exo-life,
Nope, it is not my stance. My stance is that it makes extraterrestial life more probable.

Hornblower
2013-Jul-10, 06:18 PM
but your rigid stance, that the Copernican Principle necessarily realises the existence of exo-life,

Nope, it is not my stance. My stance is that it makes extraterrestial life more probable.
My stance is that the Copernican Principle, as used in modern cosmology, does not even address such small details as the characteristics of planets and their potential life-bearing capability. As I understand it, it only says that conditions on a very large scale are similar no matter where you go in the universe, at any given time after the Big Bang. It does not rule out filaments and voids on scales of many millions of parsecs, so I do not see a conflict with having Planet Earth and its life unique.

Having said that, my gut conjecture is that the chance of similarly advanced life somewhere in the observable universe is virtually 100%, but I do not have enough information to argue for or against that scientifically.

swampyankee
2013-Jul-10, 06:50 PM
Any of several discoveries would make this entire discussion moot: evidence1 a separate origin of some past life on Earth, detectable traces, i.e., evidence, of life on an extraterrestrial body, or incontrovertible proof2 that abiogenesis on Earth must be unique. The first is going to be very difficult, as it would require either living specimens or fossils that are sufficiently detailed3 to provide believable evidence that these are not part of the tree of life as we know it. The second is going to require ongoing space exploration, which will not happen without public support and sufficient government funding4. Some people think the third question has been answered in the affirmative; I view that position as mere posturing.

-------------

1: "Evidence" as in the result of observation or experimentation. Evidence does not result from the mathematical analysis of scientific models, no matter how much we may want to think so.

2: I think this is a very high bar. I think it is possible that it will never be crossed.

3: I'd be surprised if a fossil with sufficient detail to be convincing evidence of an independent origin of life on earth is possible, let alone plausible.

4: Before you say "private enterprise," please answer a simple question: "where's the profit in searching for extraterrestrial life?" If I'm looking for iridium or helium-3 or beryllium, why should I spend the money to look for biological traces?" That costs money, and it's money that would not help my prospecting.

Selfsim
2013-Jul-10, 09:28 PM
Who would decide that and on what basis? The trusted custodians of the public conscience and creators of reality by consensus, I suppose .. journalists!
:)


Probably. Witch hunts are popular pasttime.An essential part of human culture, maybe?


Despite your claims, we know thing or two about life. While abiogenesis is indeed very murky, your sentences comes dangerously close to claiming that abiogenesis is impossible according to known laws of physics."Warning!! ..Danger, Will Robinson!!" …
… (Just kidding .. gotta have a chuckle at the term 'dangerously') :)


Nope, it is not my stance. My stance is that it makes extraterrestial life more probable.In your opinion, that is(?)

Selfsim
2013-Jul-10, 09:59 PM
My stance is that the Copernican Principle, as used in modern cosmology, does not even address such small details as the characteristics of planets and their potential life-bearing capability. As I understand it, it only says that conditions on a very large scale are similar no matter where you go in the universe, at any given time after the Big Bang. It does not rule out filaments and voids on scales of many millions of parsecs, so I do not see a conflict with having Planet Earth and its life unique.

Having said that, my gut conjecture is that the chance of similarly advanced life somewhere in the observable universe is virtually 100%, but I do not have enough information to argue for or against that scientifically.The best view a Copernican Principled, volume limited Universe can give us, is that life as we know it, is able to exist on an Earth doppelganger, (precise in every detail), which in turn, must exist in an environment identical to Earth's, in an environment identical to the Solar Systems, in an environment identical to the Solar Systems' … etc, etc.

Its very good at guiding us with what we already know.

The question it leaves us with is:
"How far, (spatially, temporally), is it to the next identical instances of all this?"

MaDeR's stance:
.. is that it makes extraterrestial life more probable. .. doesn't come solely from the Copernican Principle .. (and I'd like to thank Hornblower for pointing that out).

ASTRO BOY
2013-Jul-11, 03:54 AM
Who would decide that and on what basis?


Probably. Witch hunts are popular pasttime.


Despite your claims, we know thing or two about life. While abiogenesis is indeed very murky, your sentences comes dangerously close to claiming that abiogenesis is impossible according to known laws of physics.


Nope, it is not my stance. My stance is that it makes extraterrestial life more probable.



The Copernican principle is an assumption along with the Isotropic and Hemogenious nature of the Universe....But never the less, like the other two, a logical assumption.

The sheer size of the Universe, the stuff of life being everywhere and the near infinite numbers of stars within, certainly makes life far more probable then not, in anyone's language.

swampyankee
2013-Jul-11, 04:01 AM
I believe that present data show the Universe to be isotropic and, on sufficiently large scales, homogeneous.

Selfsim
2013-Jul-11, 05:26 AM
I believe that present data show the Universe to be isotropic and, on sufficiently large scales, homogeneous.Well that's correct. The Copernican Principle is not at all, just 'an assumption' ..

Its also semantically very easy to cite 'the stuff of life being everywhere', too .. (it rolls off the tongue/fingers quite easily) .. but it means exactly zip, because there's lots of other non-living things everywhere, made of exactly the same 'stuff'.

tnjrp
2013-Jul-11, 05:31 AM
I believe that present data show the Universe to be isotropic and, on sufficiently large scales, homogeneous.This would be applicable to the observable universe and also to much larger, probably existent but mainly unobservable "homogenous patch" of which it is a part of.

As to the original question:

Mars' surface looks quite Earth-like, apart for its utter lifelessnessMore @ "apart from looking utterly lifeless".


If somehow it could be shown with total certitude that there is no type of any life at all anywhere in the entire universe except upon the Earth, apart from deflating some ufologists and Star Trek buffs and rediverting some SETI budgets, how would this change the average astronomer's/cosmologist's/person's worldview, if at all?
Mindgames are fun. I'm sure if something replaced the Moon with a humungous crucifix of equal mass in less than a second's time there would be many more Christians.

In the case of xenolife, the pertinent point would be "how would we show with total certitude that there is no such thing". I do believe in practice it would indeed require showing that abiogenesis is so unlikely an event that it cannot possibly occur except in exactly specific conditions in an exactly specific moment in the history of the entire Universe. Could perhaps be doable and if it ever gets done, I'm sure there would be many more honest creationists.

ASTRO BOY
2013-Jul-11, 06:26 AM
Its also semantically very easy to cite 'the stuff of life being everywhere', too .. (it rolls off the tongue/fingers quite easily) .. but it means exactly zip, because there's lots of other non-living things everywhere, made of exactly the same 'stuff'.


Certainly does just roll off the tongue quite easily, and more to the point, just like the Copernican Principle, it is indeed everywhere, but really we cannot expect all of it to go to making what we call life.
But we certainly have no reason to assume with the great variety and vast extent of numbers, some of it will do what we would expect....that is go to making up life, as we know it....Oh and probably also δs we don't know it".

ASTRO BOY
2013-Jul-11, 06:37 AM
Certainly does just roll off the tongue quite easily, and more to the point, just like the Copernican Principle, it is indeed everywhere, but really we cannot expect all of it to go to making what we call life.
But we certainly have no reason to doubt with the great variety and vast extent of numbers, some of it will do what we would expect....that is go to making up life, as we know it....Oh and probably also δs we don't know it".


My edit post is not operating for some unknown reason...Another Universal mystery!!

Selfsim
2013-Jul-11, 06:43 AM
This would be applicable to the observable universe and also to much larger, probably existent but mainly unobservable "homogenous patch" of which it is a part of.Hmm .. if its applicable to 'a mainly unobservable homogenous patch', then the homogeneity of that larger patch would have to be testably verifiable .. How to do that if it is 'largely unobservable', would be a rather curious proposition, no?


In the case of xenolife, the pertinent point would be "how would we show with total certitude that there is no such thing". I do believe in practice it would indeed require showing that abiogenesis is so unlikely an event that it cannot possibly occur except in exactly specific conditions in an exactly specific moment in the history of the entire Universe. Could perhaps be doable ...The 'fine tuning problem' provides some hints about the precarious precision allowing for the existence of carbon-based life. (Ie: many apparently 'universal' physical 'constants' have aligned in our immediate region to make this so).

Are they 'universal', and are they 'constants'(?) ...

Selfsim
2013-Jul-11, 06:45 AM
My edit post is not operating for some unknown reason...Another Universal mystery!!Join the club ... (see the feedback 'redux' thread).

ASTRO BOY
2013-Jul-11, 06:46 AM
Well that's correct. The Copernican Principle is not at all, just 'an assumption' ..





Tests of the principle[edit]

The Copernican principle has never been proven, and in the most general sense cannot be proven, but it is implicit in many modern theories of physics. Cosmological models are often derived with reference to the Cosmological principle, slightly more general than the Copernican principle, and many tests of these models can be considered tests of the Copernican principle.[9]
Historical[edit]
Before the term Copernican principle was even coined, the Earth was repeatedly shown not to have any special location in the universe. The Copernican Revolution dethroned the Earth to just one of many planets orbiting the sun. William Herschel found that the solar system is moving through space within our disk-shaped Milky Way galaxy. Edwin Hubble showed that our galaxy is just one of many galaxies in the universe.Examination of our galaxy's position and motion in the universe led to the Big Bang theory and the whole of modern cosmology.



http://en.wikipedia.org/wiki/Copernican_principle




I cast no doubt on the Copernican Principle, just as I cast no doubt on ETL, existing somewhere sometime...but for both we are not 100% certain.

tnjrp
2013-Jul-11, 07:07 AM
Hmm .. if its applicable to 'a mainly unobservable homogenous patch', then the homogeneity of that larger patch would have to be testably verifiable .. How to do that if it is 'largely unobservable', would be a rather curious proposition, no?I know those of the logical postivist bend won't be satisfied by a mere theory, but the fact remains that the mainstream cosmology at the moment specifically proposes such a uniform/homogenous patch.

Selfsim
2013-Jul-11, 07:22 AM
I cast no doubt on the Copernican Principle, just as I cast no doubt on ETL, existing somewhere sometime...but for both we are not 100% certain.There is always doubt .. otherwise it wouldn't be science, would it?

Selfsim
2013-Jul-11, 07:32 AM
I know those of the logical postivist bend won't be satisfied by a mere theory, but the fact remains that the mainstream cosmology at the moment specifically proposes such a uniform/homogenous patch.Proposing ... as part of Cosmology ...

I love it when I see the CP being put to the test .. (along with the Fine Structure Constant, and the other 25 physical constants in the Standard Model). :)
'Twouldn't be a useful working principle if it wasn't tested, eh?

tnjrp
2013-Jul-11, 07:35 AM
I'm merely toeing the line of the mainstream there. You can dismiss that of course, it's your prerogative, but I don't feel there's much to discuss beyond that. Unless you have a better theory to explain the observed universe that doesn't propose a larger uniform patch of course, in which case I'll be interested to see it presented in the ATM section of the forum.


The 'fine tuning problem' provides some hints about the precarious precision allowing for the existence of carbon-based life. (Ie: many apparently 'universal' physical 'constants' have aligned in our immediate region to make this so).Typical fine tuning arguments merely extend to positing that universe is "fine-tuned for the essential building blocks and environments that life requires" (to quote Paul Davies (http://arxiv.org/pdf/astro-ph/0403050v1.pdf)). They come nowhere near the precision required to conclusively evidence that abiogenesis is a one-off event. More strict ones certainly must exist but it's another question as to how high a scientific consensus backs them.

Selfsim
2013-Jul-11, 08:19 AM
I'm merely toeing the line of the mainstream there. You can dismiss that of course, it's your prerogative, but I don't feel there's much to discuss beyond that. Unless you have a better theory to explain the observed universe that doesn't propose a larger uniform patch of course, in which case I'll be interested to see it presented in the ATM section of the forum.Hmm ... how is the explanation of the observed universe, dependent on the proposition of a much larger uniform patch?

(As an aside: This conversation may turn out to be relevant to the basis of OP assertions, (I think .. not sure, yet) ..).



The 'fine tuning problem' provides some hints about the precarious precision allowing for the existence of carbon-based life. (Ie: many apparently 'universal' physical 'constants' have aligned in our immediate region to make this so).

Are they 'universal', and are they 'constants'(?) ...Typical fine tuning arguments merely extend to positing that universe is "fine-tuned for the essential building blocks and environments that life requires" (to quote Paul Davies (http://arxiv.org/pdf/astro-ph/0403050v1.pdf)). They come nowhere near the precision required to conclusively evidence that abiogenesis is a one-off event.If they vary beyond certain thresholds however, the basic building blocks and environments that life requires, wouldn't exist. That's worthwhile checking, I would think(?)

The scales over which they then might vary, (if they do vary at all), would volume limit our Corpernican views ..


More strict ones certainly must exist but it's another question as to how high a scientific consensus backs them.I'm not sure I know what these 'strict' ones might be ... but in the case of say, Alpha (the Fine Structure Constant), if it varied by more than a couple of percent, anywhere, then the nucelosynthesis of carbon wouldn't happen. I'm not sure whether this would be a discussion requiring much 'consensus', however(?)

tnjrp
2013-Jul-11, 08:36 AM
Hmm ... how is the explanation of the observed universe, dependent on the proposition of a much larger uniform patch?Since I've been frequently chastised for being obscure, I think I have to try explaining this one more time: the scientific mainstream inflation cosmology theory (AKA Big Bang theory) that explains what we see in the observable universe also posits/proposes the existence of a much larger uniform patch. In other words, more of the same old where we can't see it's there.


I'm not sure I know what these 'strict' ones might be ...Again, I'm apparently being too obscure. "Strict ones" in this case would be specifically of the kind that more or less conclusively shows abiogenesis is a one-off event. Please recall that this requirement was a key component of the mind game proposed by OP.

HTH.

Jens
2013-Jul-11, 08:58 AM
I know those of the logical postivist bend won't be satisfied by a mere theory, but the fact remains that the mainstream cosmology at the moment specifically proposes such a uniform/homogenous patch.

I would think that most non-mainstream cosmological models would assume this as well, with the notable exception being certain creationist models.

tnjrp
2013-Jul-11, 09:03 AM
Most likely they do, if they do consent to the expansion of cosmological horizon in some way. There are almost certainly some that don't, of course.

Selfsim
2013-Jul-12, 12:18 AM
Since I've been frequently chastised for being obscure, I think I have to try explaining this one more time: the scientific mainstream inflation cosmology theory (AKA Big Bang theory) that explains what we see in the observable universe also posits/proposes the existence of a much larger uniform patch. In other words, more of the same old where we can't see it's there.'Posits' or 'proposals' are always questionable. There are several speculative ideas about the ultimate fate of an expanding universe (temporal extrapolation). What happens to the homogeneity of the obs universe at larger scales, as that expansion continues into the future, whilst constrained by the Laws of Thermodynamics, is as much related to one's underlying assumptions, as it is to anything coming from the LCDM models of mainstream Cosmology. One should remember that the LCDM model also posits the Cosmological Principle, thus I would expect it to remain consistent with that principle in its speculative extrapolations. I suspect "the existence of a much larger uniform patch" proposal, is merely reflective of that initial posit and thus, it really doesn't tell us anything new at all.

As far as spatial homogeneity beyond the present particle horizon is concerned, the mainstream models are undefined. Inferences may be drawn from CMBR flatness and they also lead to speculative ideas.

I'm still thinking about this matter (and I'm a little distracted at the moment …). I shall return on this issue .. I think it may turn out to be relevant to the OP posit .. and also highlights the way mainstream 'takes in' speculative theoretical ideas.


Again, I'm apparently being too obscure. "Strict ones" in this case would be specifically of the kind that more or less conclusively shows abiogenesis is a one-off event. Please recall that this requirement was a key component of the mind game proposed by OP.Ok .. fair enough ..

tnjrp
2013-Jul-12, 06:18 AM
As far as spatial homogeneity beyond the present particle horizon is concerned, the mainstream models are undefinedOnly if you equate "undefined" with "not empirically evidenced". This is slipping into yet another philosophy of science discussion and I frankly see no merit in such. So I'd very humbly suggest bringing the subject up in another thread -- which I shall not be attending.

Selfsim
2013-Jul-12, 08:00 AM
Only if you equate "undefined" with "not empirically evidenced". This is slipping into yet another philosophy of science discussion and I frankly see no merit in such. So I'd very humbly suggest bringing the subject up in another thread -- which I shall not be attending.Ok .. I agree that this is the topic of another discussion for elsewhere. The nature of the universe when it was younger than Planck time, is the limit of any mainstream Cosmological theoretical descriptions I know of.

Empirically speaking however, and as far as this thread is concerned, the radio galaxy TN J0924-2201, which is 12.5 billion light years away, is about the most distant carbon producing object observed to date, (AIU). This is less than a billion years after the Big Bang. As such, it could be said that the possibility of carbon based life as we know it, would be limited to the volume inside this redshift/observation (z~ 5.19), which may be pushed further back in time, as observation technology improves.

So, I guess it can be shown with 'mainstream empirical/theoretical certitude', that this is the measured limit of carbon based life's known possible extent. Beyond this redshift, it has been shown that carbon based life as we know it, cannot be explained to exist by current mainstream Cosmological theory(?) I guess we could then ponder the OP's question in the light of this, and wonder how this might change the average astronomer's/cosmologist's/person's worldview, (if at all)?

tnjrp
2013-Jul-12, 08:25 AM
Empirically speaking however, and as far as this thread is concerned, the radio galaxy TN J0924-2201, which is 12.5 billion light years away, is about the most distant carbon producing object observed to date, (AIU). This is less than a billion years after the Big BangIndeed it does strongly appear that the observable universe has been at a certain time in a state where carbon didn't exist and as such, no carbon-based life could have existed either. It was also very likely, albeit again based "only on a theory" that at a certain time in a state where no atoms of any kind existed and so no life based on anything baryonic can have existed. I however fail to see how this leads to any new big revelation so you may have elucidate a bit.

Selfsim
2013-Jul-12, 08:42 AM
Indeed it does strongly appear that the observable universe has been at a certain time in a state where carbon didn't exist and as such, no carbon-based life could have existed either. It was also very likely, albeit again based "only on a theory" that at a certain time in a state where no atoms of any kind existed and so no life based on anything baryonic can have existed. I however fail to see how this leads to any new big revelation so you may have elucidate a bit... Oh I'm not saying this leads to any new big revelations ... I'm just following the OP query, albeit along the lines of 'mainstream Cosmology theoretical and empirical constraints. If folk, (for some strange reasons), like to argue that the size of the universe 'improves the likelihood' of other instances of 'life', (and 'life' can only be defined as we know it), then 'the universe' just got a whole lot smaller than say, an infinite one!

So I wonder how that news might change the average astronomer's/cosmologist's/person's worldview, (if at all)?

tnjrp
2013-Jul-12, 08:47 AM
If folk, (for some strange reasons), like to argue that the size of the universe 'improves the likelihood' of other instances of 'life', (and 'life' can only be defined as we know it), then 'the universe' just got a whole lot smaller than say, an infinite one!I'm pretty sure but everyone knows that the observable universe is not infinite in size. I'm certainly not aware of anyone coming out to claim it is. So I guess I still fail to see the point, unless if it is yet another rehash of "anything outside of observable universe is just a theory". In which case we would again be at an impasse.

Selfsim
2013-Jul-12, 09:00 AM
I'm pretty sure but everyone knows that the observable universe is not infinite in size. I'm certainly not aware of anyone coming out to claim it is. So I guess I still fail to see the point, unless if it is yet another rehash of "anything outside of observable universe is just a theory". In which case we would again be at an impasse.


... The sheer size of the Universe, the stuff of life being everywhere and the near infinite numbers of stars within, certainly makes life far more probable then not, in anyone's language. ... Seemingly not ... in 'anyone's language' ...

tnjrp
2013-Jul-12, 09:32 AM
Universe =/= observable universe.

Selfsim
2013-Jul-12, 09:53 AM
Universe =/= observable universe.Yep ..

tnjrp
2013-Jul-12, 10:01 AM
Obviously we'll need ASTRO BOY to arbitrate which one he meant. I'm assuming the former as I always do when someone blithely throws around the term "universe" but I could be wrong as some do seem to think they are the same thing. Similarly for the OP of course but wd40 is not known for elaborating on his comments so it may be a long wait.

ASTRO BOY
2013-Jul-12, 11:35 AM
__________________________________________________ __________________________________________________ __________________________________________________ ______________________
Originally Posted by ASTRO BOY
... The sheer size of the Universe, the stuff of life being everywhere and the near infinite numbers of stars within, certainly makes life far more probable then not, in anyone's language.
__________________________________________________ __________________________________________________ __________________________________________________ ____________________________

__________________________________________________ __________________________________________________ __________________________________________________ ______________________
Obviously we'll need ASTRO BOY to arbitrate which one he meant. I'm assuming the former as I always do when someone blithely throws around the term "universe" but I could be wrong as some do seem to think they are the same thing. Similarly for the OP of course but wd40 is not known for elaborating on his comments so it may be a long wait.
__________________________________________________ __________________________________________________ __________________________________________________ ___________________________



... Seemingly not ... in 'anyone's language' ...



Umm, I made that statement in support of Mader in post 140, certainly not meaning the observable Universe which is only about 96 billion L/years in diameter.
Certainly not in reply to the following which Selfism seems to have somehow mixed up....
It applies to the Universe as a whole.

__________________________________________________ __________________________________________________ __________________________________________________ __________________________
I'm pretty sure but everyone knows that the observable universe is not infinite in size. I'm certainly not aware of anyone coming out to claim it is. So I guess I still fail to see the point, unless if it is yet another rehash of "anything outside of observable universe is just a theory". In which case we would again be at an impasse.
__________________________________________________ __________________________________________________ __________________________________________________ ___________________________

Paul Wally
2013-Jul-12, 12:08 PM
Empirically speaking however, and as far as this thread is concerned, the radio galaxy TN J0924-2201, which is 12.5 billion light years away, is about the most distant carbon producing object observed to date, (AIU). This is less than a billion years after the Big Bang. As such, it could be said that the possibility of carbon based life as we know it, would be limited to the volume inside this redshift/observation (z~ 5.19), which may be pushed further back in time, as observation technology improves.


See underlined. That should be "the earliest carbon ..." not the most distant. It means the earliest carbon formed 12.5 Billion years ago, but that says nothing about the spatial distribution of carbon in the universe. Logic suggests that if there is carbon more than your 12.5 Billion light years away, then the light from that carbon must still reach us, so this has nothing to do with "our observation technology" either.

Swift
2013-Jul-12, 09:51 PM
There were direct, explicit relationships describing the universal laws of motion, and the universal laws of gravitation and matter, which was known to be applicable for describing what happens to matter and gas in space. Firm physical predictions about the formation of planets could therefore be made from models based on these laws.

There are no equivalent laws describing the processes which result in the elements and inorganic compounds coming together to form life. Firm predictions from science, thus cannot be made about its formation. Tentative, speculative predictions about non-terrestrial life, must treat the existence of life phenomenologically, and seek out evidence elsewhere, in order for the idea to be extracted from the realm of speculation.

There's a big difference between the two scenarios, which you cite as being analogously equivalent, (and use to assert others being 'wrong'). Having an opinion about it was fine .. but it seems your opinion has now shifted to declaring others to be 'wrong' about theirs(?)

Consider: there is no physical law, which explains why there has only ever been one unique MaDer (as far as we know).
I think you overstate planet formation and understate life formation.

The "universal laws of motion" and "the universal laws of gravitation and matter" (whatever a law of matter is) are not sufficient to describe planet formation. There are models of planet formation, that incorporate such laws, and also incorporate a variety of both observations and assumptions, that make predictions both about the general formation of planets (from gas and dust clouds) and types of planets that may form. Such models did exist before exoplanets were observed and did predict their existence. The existence of exoplanets has now been experimentally confirmed (though much of the data is not from direct observation of such planets, but indirect observation from transits and effects on the motion of their stars).

You are correct that there are no laws that describe the formation of life; but there are no laws that describe planet formation (note I am using a pretty strict defintion of law; F = ma is a law). However, we have several pretty good models of the formation of pre-biotic compounds and of life, and a lot of experimental evidence for various aspects of those models (both in the laboratory and in the field). As MaDeR said, "our knowledge about universe, laws of physics etc indicate life should be normal byproduct of laws of this universe". I think that is a very well phrased statement. I think it very equivalent to the case of exoplanets before their observation.

MaDeR
2013-Jul-13, 11:29 AM
If folk, (for some strange reasons), like to argue that the size of the universe 'improves the likelihood' of other instances of 'life',
Of course it improves. For given chance of life originating on some planet (for simplification lets say this chance is per star), universe twice as large would provide twice as much opportunites, as there will be twice as much stars.

There is only one case where size of universe does not matter: assuming a priori there can be only one life instance ever, period. Not that I am pointing fingers at anyone, oh nooo...

Paul Beardsley
2013-Jul-13, 03:09 PM
Not that I am pointing fingers at anyone, oh nooo...

I should hope not. If you think someone is saying that, please indicate the post.

Selfsim
2013-Jul-14, 02:10 AM
I think you overstate planet formation and understate life formation.

The "universal laws of motion" and "the universal laws of gravitation and matter" (whatever a law of matter is) are not sufficient to describe planet formation. There are models of planet formation, that incorporate such laws, and also incorporate a variety of both observations and assumptions, that make predictions both about the general formation of planets (from gas and dust clouds) and types of planets that may form. Such models did exist before exoplanets were observed and did predict their existence. The existence of exoplanets has now been experimentally confirmed (though much of the data is not from direct observation of such planets, but indirect observation from transits and effects on the motion of their stars).

You are correct that there are no laws that describe the formation of life; but there are no laws that describe planet formation (note I am using a pretty strict defintion of law; F = ma is a law). However, we have several pretty good models of the formation of pre-biotic compounds and of life, and a lot of experimental evidence for various aspects of those models (both in the laboratory and in the field). As MaDeR said, "our knowledge about universe, laws of physics etc indicate life should be normal byproduct of laws of this universe". I think that is a very well phrased statement. I think it very equivalent to the case of exoplanets before their observation.Y'know, upon deeper reflection, I've come to the conclusion that in the strictest sense, (which seems to be what I am being called upon to come up with here), I don't think any Physical Theory ever formally makes predictions on the existence of anything. The whole point, originally raised by MaDeR, (I think?), is thus a completely meta-physical (philosophically based) issue.

Theories make predictions within their own paradigm of applicability which in itself, is synthesised by science .. but this is completely separate from some speculated existence of some 'physical reality', which science theory cannot, and never will, access. In fact debating such questions of 'physical existence' is almost a complete waste of time in the strictest scientific paradigm.

In fact, the closest one can come to 'existence', whilst staying within the scientific paradigm, is empirical testing and its results. This basically brings me back to what I said way back, which is that science must treat the 'existence' of life by making use of largely incomplete speculative hypotheses, leading to its origin status as a largely unexplained phenomenon, (like gravity is in Newtonian Gravitation), and conduct exploration for other evidence of it .. (or, better still, explore with the view to gaining empirical knowledge of the (observable) universe .. and in so doing, make note of when/if 'life' happens to turn up).

I don't have any issues with others' opinions of my views (like yours above) … but I do think we need to distinguish that the basis of 'predicting' the existence of something, is Meta-Physics .. ie: not Science.

PS: Please excuse my impending absence (and further comments following this post .. I have other pressing priorities). Rgds

Swift
2013-Jul-14, 04:16 AM
Y'know, upon deeper reflection, I've come to the conclusion that in the strictest sense, (which seems to be what I am being called upon to come up with here), I don't think any Physical Theory ever formally makes predictions on the existence of anything. The whole point, originally raised by MaDeR, (I think?), is thus a completely meta-physical (philosophically based) issue.

I'm sorry, but that's nonsense. For example, the existence of the Higgs Boson was predicted and has now been confirmed.

If you want to play semantics, I guess, for example a model of planet formation might be said to assume planets forms and shows a mechanism for their formation, and thus doesn't "predict" planets form.

I don't think a comparison of understanding planet formation and life formation is a game of metaphysics, as you seem to believe.

Selfsim
2013-Jul-14, 06:26 AM
I'm sorry, but that's nonsense. For example, the existence of the Higgs Boson was predicted and has now been confirmed.The particle known as the 'Higgs Boson' was defined in the Standard Model. The theory predicted it to have a 'mass' in ranges which were constrained by that model. A signal was isolated within that mass range. The theory says nothing about existence. The Standard Model might be our best tool which results in considerable practical use (as it is highly consistent in explaining our observations) .. but 'existence' is not a claim made within its domain. The experiment and its results, verified the prediction made by the theory. As I said, empirical results get us as close to what we call 'reality', as we can arguably get .. but science never makes claims on 'existence' in a reality beyond its descriptive abilities and its definitions. There is no 'reality' to 'discover', beyond what science can describe to us or access, in the language used in the theory in question, because that is not useful to science. Needless to say each theory has its own terms and meanings. Comparisons between theories', predictive abilities, (or in this case, a planetary theory's and an exo-life hypothesis') is quite meaningless, particularly so, if the only linkage between the two, is some speculative, indirect inference that there is some arbitrary reality backdrop underpinning both. Physics Laws may underpin both, but clearly this is not sufficient to explain abiogenesis, even if abiogenesis occurs within the purview of such Laws. There is also no established causal process/mechanism at appropriate scales, between the Earth's prebiotic environment, and the emergence of life (Abiogenesis), connecting both Planetary Formation theory and life emergence, thus the comparison is made even more disparate and disconnected when this is considered.


If you want to play semantics, I guess, for example a model of planet formation might be said to assume planets forms and shows a mechanism for their formation, and thus doesn't "predict" planets form. This goes beyond just semantics, (although the mathematical basis of quantified theories is all about semantics). And I am not attempting to playing with semantics. The term 'existence' was cited by MaDeR .. (not me). 'Planet' is an arbitrary definition, although it was fairly clear what it was, when planet-like objects were included in Planetary Formation Theory models which posited them. The term was thus given its meaning within Planetary Formation Theory. It may have a completely different meaning within exo-life hypotheses, too ('exo-moons', 'habitable environments', etc). Planets 'exist' within the purview of the scientific toolset, and is given meaning in the models created by science which specifically reference them. As such, anything predicted by such a model, is subject to the assumptions pre-established by that model and by the meaning given them, within it. Uncertainty is always part of the models, and uncertainties are an intrinsic part of experimental measurement. Sometimes uncertainties exceed the mean value of some measurement. That's all part of the scientific paradigm. If a prediction made by a theory is independently verified by repeated experiment or measurement, then the theory is validated (and becomes practically useful). There is nothing in that, about 'existence' in some arbitrary reality, or the validity of some other theory or hypothesis. What remains is a practically useful theory. Planetary theory is one such theory, but the theory is the focus, and becomes useful once experiment or measurement validates its predictions.

Exo-life 'existence' is only presently the subject of speculative hypotheses. None of these have been validated, (ie: beyond Earth). The hypotheses therefore remain purely speculative only. Predictions made by them are not analogous to Planetary Formation Theory predictions (at the time they were made), because Planetary Formation Theory was already validated by the measurement/observation of 'planets' within our own in the 'Solar System'. The hypothesis concerning the formation of planets around other stellar systems, was not validated until exo-planet measurements were made, which verified the hypothesis outside of the Solar System. (Come to think of it, (and as an aside), there is presently some question about whether all 'exo-planet' measurements are actually 'planets', too. See here. (http://phys.org/news/2013-07-simulation-disk-anomalies-stars-planets.html) This is uncertainty in measurements in action, which I mentioned above:
Here we report linear and nonlinear modelling that shows that dust–gas interactions can produce some of the key patterns attributed to planets. We find a robust clumping instability that organizes the dust into narrow, eccentric rings, similar to the Fomalhaut debris disk. The conclusion that such disks might contain planets is not necessarily required to explain these systems.This study serves to highlight that the discovery of exo-planets, only serves as a way of validating a theory … not as a way of validating existence of some object in some arbitrary reality, which is precisely my point.


I don't think a comparison of understanding planet formation and life formation is a game of metaphysics, as you seem to believe.I encourage you to look more closely into the role Scientific Theories and hypotheses play in science. There are many good threads in the Science and Technology Forum explaining these distinctions here at CQ. One particularly good post is here. (http://cosmoquest.org/forum/showthread.php?140984-Justified-True-Belief&p=2100663#post2100663) Another sequence of relevant posts is here (http://cosmoquest.org/forum/showthread.php?138785-*Evidence*-that-our-universe-is-a-simulation/page2).

ASTRO BOY
2013-Jul-14, 08:40 AM
Exo-life 'existence' is only presently the subject of speculative hypotheses. None of these have been validated, (ie: beyond Earth). The hypotheses therefore remain purely speculative only. Predictions made by them are not analogous to Planetary Formation Theory predictions (at the time they were made), because Planetary Formation Theory was already validated by the measurement/observation of 'planets' within our own in the 'Solar System'. The hypothesis concerning the formation of planets around other stellar systems, was not validated until exo-planet measurements were made, which verified the hypothesis outside of the Solar System. (Come to think of it, (and as an aside), there is presently some question about whether all 'exo-planet' measurements are actually 'planets', too. See here. This is uncertainty in measurements in action, which I mentioned above:


I encourage you to look more closely into the role Scientific Theories and hypotheses play in science. There are many good threads in the Science and Technology Forum explaining these distinctions here at CQ. One particularly good post is here. (http://cosmoquest.org/forum/showthread.php?140984-Justified-True-Belief&p=2100663#post2100663) Another sequence of relevant posts is here (http://cosmoquest.org/forum/showthread.php?138785-*Evidence*-that-our-universe-is-a-simulation/page2).


To use an analogy your stance on the "straight down the line" and "semantic" approach to science, could be akin to a race horse wearing blinkers, to focus his attention on the business of racing and ignoring anything else.
That may work with race horses, it doesn't in my opinion work with science and the scientific method.
You treat speculation as apparently something to be abhored and dangerous to science and the scientific method, no matter how well supported by indirect evidence that speculation is.
Even the evidence in the history of science appears to be ignored with your approach and strict adherence to the scientific method.

You are wrong...and that is supported by most astronomers/cosmologists and Astro-physicists.
Yes certainly some speculation will always be just that, and will remain so forever......some, not all, because without some speculation and Imagination, science will stagnate.
We have much indirect evidence and data to formulate logical speculation that ETL should exist...........That should be and is thankfully considered by most reputable scientists of all pursasions.

We have near infinite extent in volume and numbers, the raw materials that make up life, other scientific assumptions such as Isotropy and homogenity, and the narrow constants that support our Universe also support the arising and evolution of life.
We have barely stepped outside of our planetary cradle to search and verify any other life as yet, and even in a hundred years time, when we should be considering manned stellar travel, time and distance will always be barriers.

All those scientists, cosmologists and Astro-physicists know we do not as yet have any direct evidence for ETL, but the vast majority of those scientists, cosmologists and Astro-physicists also believe that life should exist elsewhere....they know for certain, there is no reason why life elsewhere does not, has not or cannot evolve similar to the way it did on Earth.

If this "straight down the line" approach, was universal among all scientists, I would suggest we would not be as scientifically advanced as we are today.

And yes of course, the walls of the box are necessary in the long run, and speculation, Imagination, and Innovation, needs to run the gauntlet [so to speak] in satisfying ones peers.

Selfsim
2013-Jul-14, 09:23 AM
See underlined. That should be "the earliest carbon ..." not the most distant. It means the earliest carbon formed 12.5 Billion years ago, but that says nothing about the spatial distribution of carbon in the universe. Logic suggests that if there is carbon more than your 12.5 Billion light years away, then the light from that carbon must still reach us, so this has nothing to do with "our observation technology" either.:confused:

There is a limit, going backwards in time, as we look further out in the obs. universe, beyond which carbon could not form. This 'limit' also constrains the possible existence of carbon based life. The most distant galaxies are extremely faint. They require special technologies to observe their spectral signatures. TN J0924-2201 was one of 'em.

Paul Wally
2013-Jul-14, 11:02 AM
:confused:

This 'limit' also constrains the possible existence of carbon based life. The most distant galaxies are extremely faint. They require special technologies to observe their spectral signatures. TN J0924-2201 was one of 'em.

No, why should how far we can look into the past limit the spatial extent of carbon based life? So what if some distant galaxies look faint to us? That has nothing to do with whether there's carbon based life or not.

Trakar
2013-Jul-14, 07:21 PM
Mars' surface looks quite Earth-like, apart for its utter lifelessness.

If somehow it could be shown with total certitude that there is no type of any life at all anywhere in the entire universe except upon the Earth, apart from deflating some ufologists and Star Trek buffs and rediverting some SETI budgets, how would this change the average astronomer's/cosmologist's/person's worldview, if at all?

Science does not deal in "total certitude," such would be an unscientific finding and therefore without much meaning except to those to whom such beliefs are consistent with their pre-existent ideologies.

Selfsim
2013-Jul-14, 08:23 PM
No, why should how far we can look into the past limit the spatial extent of carbon based life? So what if some distant galaxies look faint to us? That has nothing to do with whether there's carbon based life or not.Who said anything about spatial extent of carbon? That seems to be your point .. not mine. Causality boundaries set the upper limits here. The redshift detection issues render this a moot point anyway, unless you introduce science fiction .. which is not realistic (of course). I won't be involved in that discussion …

Paul Wally
2013-Jul-14, 10:36 PM
Who said anything about spatial extent of carbon?
You said in post #159:


As such, it could be said that the possibility of carbon based life as we know it, would be limited to the volume inside this redshift/observation (z~ 5.19), which may be pushed further back in time, as observation technology improves.

Volume is spatial.


That seems to be your point .. not mine.
Nope, see above.


Causality boundaries set the upper limits here. The redshift detection issues render this a moot point anyway, unless you introduce science fiction .. which is not realistic (of course). I won't be involved in that discussion …

These things that you mention don't 'limit' the 'volume' wherein carbon based life can exist. They do limit what we humans can currently observe, but they place no limits on the existence of carbon based life anywhere else in the universe. It's simply not relevant to the issue.

Colin Robinson
2013-Aug-11, 01:47 AM
A scenario presented near the beginning of this thread:


A possibly more interesting scenario would be if we had a pretty good idea of how abiogenesis worked, and we were able to predict with confidence that a fairly large number of specific worlds should be teeming with life, but each time we get around to exploring one of them it turns out to be barren, leading us to believe that the universe is probably empty.

A scenario like that, if it happened in fact, would logically be taken as a falsification of the model of abiogenesis which predicted teeming life on those specific worlds.

Which is actually an important part of what it means when a theory or model predicts something. It is not a matter of certainty. The predictions are always contingent on the theory itself being correct.

If observations do not match the prediction, then the theory will have to be changed.

Selfsim
2013-Aug-11, 10:20 PM
A scenario presented near the beginning of this thread:
A possibly more interesting scenario would be if we had a pretty good idea of how abiogenesis worked, and we were able to predict with confidence that a fairly large number of specific worlds should be teeming with life, but each time we get around to exploring one of them it turns out to be barren, leading us to believe that the universe is probably empty.

A scenario like that, if it happened in fact, would logically be taken as a falsification of the model of abiogenesis which predicted teeming life on those specific worlds.

Which is actually an important part of what it means when a theory or model predicts something. It is not a matter of certainty. The predictions are always contingent on the theory itself being correct.

If observations do not match the prediction, then the theory will have to be changed.Welcome back, Colin .. :)

I think that, was Paul Beardsley's point .. ie: that the scenario posed, was at least, able to be addressed by the scientific process, and could also be bounded (partially) by we already know is possible. (The OP scenario fails on both of these measures). The 'interesting' part would be watching folk come to the realisation that such a best 'theory', did not match the evidence at hand.

Having said this, I don't believe that abiogenesis will ever be more than an hypothesis until, (or, if), other life instances are found elsewhere. We cannot reconstruct our own past in sufficient detail and precision, to make any predictions at the necessary molecular levels, 'with confidence'. (The audit trail of information needed to do so, for our own life instance, is long gone). So, I think the abiogenesis hypothesis would 'live on' as an hypothesis.

Lab discoveries would likely impose restrictions on the initial conditions, which could also be highly unlikely, leaving any scenarios produced by labs, subject to large uncertainties, (and opinions), also.

Paul Beardsley
2013-Aug-11, 10:35 PM
Yeah, what bugs me about the premise of this thread is that it makes as much sense as someone arriving on a sailboat to announce that there's no such thing as wind... and the further assumption that a question is not obliged to make sense if it's preceded by "what if".

Selfsim
2013-Aug-11, 11:02 PM
Yeah, what bugs me about the premise of this thread is that it makes as much sense as someone arriving on a sailboat to announce that there's no such thing as wind... and the further assumption that a question is not obliged to make sense if it's preceded by "what if".Yep .. totally agree .. 'junk speculation' ..