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View Full Version : Search for Signs of Alien Civilizations in 100,000 Galaxies Returns Empty Handed



Fiery Phoenix
2015-Apr-21, 05:34 PM
From Scientific American (http://www.scientificamerican.com/article/alien-supercivilizations-absent-from-100-000-nearby-galaxies/):



[A team of Penn State researchers] looked for objects that were optically dim but bright in the mid-infrared—the expected signature of a galaxy filled with starlight-absorbing, heat-emitting Dyson spheres. After using software to automatically sift through some 100 million objects in the WISE catalogue, Wright’s student Roger Griffith examined the remaining candidates by hand, culling those that weren’t galaxies or that were obvious instrumental artifacts.
...
The result was about 100,000 galaxies, with about 50 in particular that emitted much more heat than light. Jessica Maldonado, a student at California State Polytechnic University, Pomona, then scoured the astronomical literature to determine what was already known about those top candidates. Many of them were well studied, and can be explained as pairs of galaxies in the process of merging or as isolated “starburst” galaxies—two processes that can heat galactic quantities of light-blocking dust to generate powerful infrared glows. According to the researchers, an additional 90 galaxies with less extreme heat-to-light ratios warrant further study but, by and large, the results are null. “On Kardashev’s scale, a type 3 civilization uses energy equal to all the starlight produced by one galaxy,” Wright says. That would equate to an infrared-bright galaxy seemingly bereft of stars. “We looked at the nearest, largest 100,000 galaxies we could find in the WISE catalogue and we never saw that. One hundred thousand galaxies and not one had that signature. We didn’t find any type 3s in our sample because there aren’t any.”

But there is another interesting argument raised:


But as rich as the scientific literature is with ideas, some of the most fascinating ones come instead from science fiction. Drawing from Arthur C. Clarke’s famous quip that “Any sufficiently advanced technology is indistinguishable from magic,” in 2011 the science fiction author Karl Schroeder coined an all-too-plausible reason for the apparent absence of aliens: “Any sufficiently advanced technology is indistinguishable from nature.” In this view the future of technology would not consist of star-hopping civilizations spreading like wildfire through galaxies, disassembling planets and smothering suns, but rather of slow-growing cultures becoming more and more integrated with their natural environments, striving for ever-greater efficiencies and coming ever-closer to thermodynamic equilibrium.

In other words:



“SETI is essentially a search for technological waste products,” Schroeder has written. “Waste heat, waste light, waste electromagnetic signals—we merely have to posit that successful civilizations don’t produce such waste, and the failure of SETI is explained.

Dyson also had a few words on this, which essentially amount to the same thing as the above quote.

The actual paper can be found here in the Astrophysical Journal:

http://iopscience.iop.org/0067-0049/217/2/25/article

Noclevername
2015-Apr-21, 09:08 PM
“SETI is essentially a search for technological waste products,” Schroeder has written. “Waste heat, waste light, waste electromagnetic signals—we merely have to posit that successful civilizations don’t produce such waste, and the failure of SETI is explained.

I don't buy that argument. There are diminishing returns; at some point chasing after every stray bit of waste heat becomes far more trouble than it's worth.

How about; There's no type 3 civilizations detected because even advanced civilizations just don't need the energy of whole galaxies to survive. And the failure of SETI is explained.
There's no type 3 civilizations detected because no one who uses one is within 100,000 galaxies of us. And the failure of SETI is explained.
Nobody's home. And the failure of SETI is explained.

Jens
2015-Apr-21, 11:04 PM
I find it hard to believe that Scientific American would allow "a team lead by" to stand uncorrected, in the lead paragraph no less. What is the world coming to?

Jens
2015-Apr-21, 11:09 PM
But to be fair, the article has been changed. At Scientific American it seems to be a completely different text, and the press release was also modified.

Fiery Phoenix
2015-Apr-21, 11:21 PM
But to be fair, the article has been changed. At Scientific American it seems to be a completely different text, and the press release was also modified.
Actually, the typo is still there in their 4th paragraph. I think it might have been the way I arranged the quotes that's confusing; there's just so much info in there. I will edit it now. Thanks for the heads-up!

Reality Check
2015-Apr-22, 01:18 AM
From Scientific American (http://www.scientificamerican.com/article/alien-supercivilizations-absent-from-100-000-nearby-galaxies/):

Scientific American is a popular science magazine so it emphasizes the most newsworthy implication of that paper. The boring implication is just that civilizations would not build Dyson Spheres (http://en.wikipedia.org/wiki/Dyson_sphere#Dyson_shell) because they are impossible to build (e.g. no material is strong enough) or impractical (e.g. a typical solar system does not have enough material; the expense of clearing out/protecting from potential impacting bodies is too high).

John Mendenhall
2015-Apr-22, 01:31 AM
Actually, the typo is still there in their 4th paragraph. I think it might have been the way I arranged the quotes that's confusing; there's just so much info in there. I will edit it now. Thanks for the heads-up!

Obviously, they need to get the lead out.

John Mendenhall
2015-Apr-22, 01:42 AM
More on topic, aren't our explanations for the lack of success with SETI getting a little strained? There is one beautifully simple explanation: there aren't any ETI's.

Can you feel the cold wind of 3.2 degrees absolute blowing on your neck?

marsbug
2015-Apr-22, 07:16 AM
I'm curious to read everyone putting this in terms of SETI succeeded or failed. The paper reports finding 50 objects that would be consistent with a K type 2. something civilisation using up to 85% of their galactic energy emitted, and 90 or so that would be consistent with a civilisation using up to 50% of their galactic energy. The paper actually recommends that these objects be followed up using either SETI or more conventional resources, because even though ETI activity is only one of many explanations, these are unusual objects, new to astronomers, and potentially very interesting regardless of whether intelligence had a hand in them.

WRT more conventional SETI, there have been a number of signals detected that fitted the bill but never repeated. The day to day signals of the type given off by Earth wouldn't be detectable to anyone above the background noise (I'll hunt down a reference for that if you like) if they were much further away than proxima centauri, and intentional efforts would only appear once in a hypothetical ETI's sky - unless an ETI was building massive omni directional transmitters the same would apply to their signals.

Based on what I've generally read I'd say that intelligent, technological, life that is both aware of us and interested in communicating with us certainly seems to be rare. However it's still too early to decide 'we are alone', and will be for a very long time to come.

WRT to the paper in the OP, it rules out there being any galactic empires using all the starlight of their galaxy, in a relatively small sample of 100,000 galaxies. It leaves the door open on there being a small number of civilisations using some significant fraction of their galaxies light in that sample. Even one in that sample of 100,000 would a significant number universe-wide. It's not a failure, and had it found a sky full of objects that looked like a dyson englobed galaxy would be expected to look it would not have been a success - that would have needed many many years of follow up observations, ruing out all possible natural explanations. Science doesn't work by having one be all and end all massive study that settles things once and for all, despite the fact that this is what people seem to want it to do!

Noclevername
2015-Apr-22, 08:49 AM
Scientific American is a popular science magazine so it emphasizes the most newsworthy implication of that paper. The boring implication is just that civilizations would not build Dyson Spheres (http://en.wikipedia.org/wiki/Dyson_sphere#Dyson_shell) because they are impossible to build (e.g. no material is strong enough) or impractical (e.g. a typical solar system does not have enough material; the expense of clearing out/protecting from potential impacting bodies is too high).

IIRC, they were searching for a real Dyson Sphere, the original version formulated by Dyson; a dense swarm of orbital stellar-power satellites. Not a shell.

KABOOM
2015-Apr-22, 12:37 PM
K-3 civilizations are much more improbable than any of the following:

Abiogenesis
Panspermia
Evolution to multi-cellular species
Evolution to species with brains
Evolution to "intelligent" species
Evolution to advanced technological society.
Ability to colonize a near by planet.

Beyond the above the simple answer may be simply the distances are too vast, the investment/payback too daunting and frankly the feasibility of implementation/construction etc too difficult (perhaps impossible at the galactic level).

Searching for K3 civilizations is a search for a quick fix. The ability to really search for life requires following a number of very tiny (and still expensive and challenging) baby steps -- starting with a comprehensive exploration of our own solar system.

John Mendenhall
2015-Apr-22, 03:18 PM
K-3 civilizations are much more improbable than any of the following:

Abiogenesis
Panspermia
Evolution to multi-cellular species
Evolution to species with brains
Evolution to "intelligent" species
Evolution to advanced technological society.
Ability to colonize a near by planet.

Beyond the above the simple answer may be simply the distances are too vast, the investment/payback too daunting and frankly the feasibility of implementation/construction etc too difficult (perhaps impossible at the galactic level).

Searching for K3 civilizations is a search for a quick fix. The ability to really search for life requires following a number of very tiny (and still expensive and challenging) baby steps -- starting with a comprehensive exploration of our own solar system.

Complete agreement here. Europa calls for exploration

Colin Robinson
2015-Apr-23, 03:06 AM
K-3 civilizations are much more improbable than any of the following:

Abiogenesis
Panspermia
Evolution to multi-cellular species
Evolution to species with brains
Evolution to "intelligent" species
Evolution to advanced technological society.
Ability to colonize a near by planet.

Beyond the above the simple answer may be simply the distances are too vast, the investment/payback too daunting and frankly the feasibility of implementation/construction etc too difficult (perhaps impossible at the galactic level).

Searching for K3 civilizations is a search for a quick fix. The ability to really search for life requires following a number of very tiny (and still expensive and challenging) baby steps -- starting with a comprehensive exploration of our own solar system.

"Still expensive" is right exploration of our own solar system by means of orbiters and rovers is very much more expensive that searching thru existing astronomical data for any possible signs of K3 civilisations as these researchers have done. Still, I'd agree the evolution of a high-technology civilisation on any given planet is less probable than that of microbes, and that astrobiological exploration of the solar system is more likely to bring substantial results than searching for extraterrestrial intelligence by looking for signs of its technology.

Jens
2015-Apr-23, 05:28 AM
Scientific American is a popular science magazine so it emphasizes the most newsworthy implication of that paper. The boring implication is just that civilizations would not build Dyson Spheres (http://en.wikipedia.org/wiki/Dyson_sphere#Dyson_shell) because they are impossible to build (e.g. no material is strong enough) or impractical (e.g. a typical solar system does not have enough material; the expense of clearing out/protecting from potential impacting bodies is too high).

I completely agree. To me the possibility that an intelligent species could use the energy (or would want to use the energy) or a whole galaxy seems like fantasy. The distances are so great that nothing you did would really have any impact and there is no way that you would possibly govern a system where it takes millions or years to get from one place to another. There is so much energy available just from star burning without doing anything particularly complicated that it would seem utterly pointless to try to harness the energy of a galaxy.

malaidas
2015-Apr-23, 07:43 AM
It's not only more improbable, it's also a matter of our own technical limitations, and realistic Needs for a civilisation

1) we are seeing the past , not the current and iN any case we are ruling out only civilisations that are galactic spanning.
2) the chances are no species would need to capture all the energy in this way. except perhaps for a few stars. As not all systems will contain viable interest. You have to think that no matter what form such an ETI would take, cost/benefit and economy will play their part. ThUs even if they had the capacity to do so, it may well be that it is simply not desirable for them to.

n.b. by economy I don't imply a necessity for money. Simply a matter of priorities and subjective values.

ETA: also I have problems seeing the viability of a single galactic spanning civilisation. If we were to take the MW as typical for illustration only. Then we are talking aprox 100 billion systems separated by unimaginable distance. This would probably cause insurmountable adminstration problems, a lack of viable trade links between distant systems and independently evolving cultures and of course language. Such could not maintain a monolithic structure so far as I can see. rather breaking down into smaller groups by shere practicality and a large dose of entropy. It's tempting to think of people zipping round the cosmos at whim, but it is incredibly unlikely to be case at least as a general rule. Other more important factors relating to a species social structure will come into play. In other words it's as much or perhaps more about other factors as about the technical ability to do it.

I accept that we only have ourselves to go on, but these factors seem to me to be a necessity for any advanced civilisation and they play havoc with the idea of a large % of the stars being harvested in this fashion.

malaidas
2015-Apr-23, 09:54 AM
A prosaic example of language changes which could occur even with the best technology. All you need is a disconect which is highly likely in such a civilisation, even if you could stargate etc instantly between any 2 locations within the galaxy.

first of all consider someone in the 60's/70's before the advent of the mobile phone. If you said Lol to someone, they would probably be rather confused in context, but they would take a completely different meaning to the term, as in 'lolling off to sleep'. So here is a simple example of language evolution over a short period of time, in the digital age

However you might say, so what this is becuase it was before the mobile phone and now all people understand what we mean and yes I agree, because there is a connection. So what if two cultures with mobile phones developed independently from a single source, now one culture might have come up with LOL and the other SIP (snigger in pants). Both of which had originally different meanings in different context. It would cause confusion. Now see this over 1000 years or more as different branches of the 'civilisation' are branching out in different directions, having little or no contact with each other. Language will not remain the same regardless of any technical solution that would attempt to retard the changes and over time the impotus to keep trying to maintain the original language will be lost except to a few academics. The main reason for this is that there would be little or no reason for a member of branch A to visit branch B, economics will demand that trade be more likely to nearby systems than far away systems (as a general rule).

If you want to look at this a different way consider how colonisation is likely to occur and the inherent structure it will lead to. You will have a mother world for the current colonisation, and the colony will be dependent upon it at least at first. They will need to trade back their resources for the things they need, not stock pile to build a Dyson sphere. Indeedwhat they will create is energy gathering facilities appropriate for their needs, not the overkill of capturing a large % of the solar output. The net effect is that only those colonies that grow to sufficient size to need such, will create such and the size of the colony is liable to depend upon its location, resource availability etc.

I think what I am trying to say is this. I would not expect to find what they were looking for in the first place, however this has no play on the question of the existence of ETI. What was being looked for was an idealisation of a class 3 civilisation that is most likely to be pretty much a pipe dream.

ETA: as an even more pertinent difference consider the word 'Pavement'. A British person and an American will take an entirely different meaning to the word and one which might even prove horrific if it isn't realised in the wrong circumstance. Consider if an American told a British person first visiting the states, 'that you're not allowed to walk on the Pavement'. The reason being is that what British People call the 'Pavement' is what Americans call the 'Side Walk' and what Americans call the 'Pavement' , the British call the 'Road'. Simply different meanings to the same word that have arisen over a few centuries, despite having a common lingual source. There is no reason to suspect that any species capable of reaching class 3 status will not suffer the same basic problems, because an intelligent species needs to be able to develop language to deal with the concepts it comes up with, it cannot have a fixed vocabulary.

Without a common ability to understand each others words, there can be no shared culture and no single civilisation. These separate branches will each branch off in their own particular ways, some may not even develop the ability create a dyson sphere, instead finding a way to use artificial fusion plants for their needs, some may decide to cut back on their energy usage in favour of different principles, some may indeed develop the dyson sphere, but then find that the shere size of their sphere means that they have no need to colonise further, especially if they find a way to replicate all the things they need.... the point is that the thing they are looking for is perhaps one of the least likely events to occur, so to use it as an argument against ETI is just invalid.

Jens
2015-Apr-23, 10:45 PM
Just FYI, I'm American and I don't use pavement to mean road. I use it simply to refer to a hardened surface that you walk on, so it could be a sidewalk or a road or a basement.

I agree with the point about language changes.

malaidas
2015-Apr-23, 11:49 PM
Fair enough this may be dialectical, my knowledge of this is based upon my brother who lives in San Jose.

Colin Robinson
2015-Apr-24, 12:59 AM
Without a common ability to understand each others words, there can be no shared culture and no single civilisation. These separate branches will each branch off in their own particular ways, some may not even develop the ability create a dyson sphere, instead finding a way to use artificial fusion plants for their needs, some may decide to cut back on their energy usage in favour of different principles, some may indeed develop the dyson sphere, but then find that the shere size of their sphere means that they have no need to colonise further, especially if they find a way to replicate all the things they need....

That's like the story of the tower of Babel, where cooperation broke down because of differences in language...


the point is that the thing they are looking for is perhaps one of the least likely events to occur, so to use it as an argument against ETI is just invalid.

There's always a danger in becoming so fixated with a particular model or conjecture about extraterrestrial intelligence or extraterrestrial life, that if and when the conjecture fails people jump to the conclusion that there is no ETI anywhere, or no ETL anywhere...

E.g. Percival Lowell's theories about canal-building Martians caught the world's imagination, then after they turned out to be wrong, there was a time when an ETI search project which had nothing to do with Mars could be derided in the US Senate as a "Great Martian Chase".

marsbug
2015-Apr-24, 06:39 AM
Though I was quick to point out that the lack of any totally dysonian galaxies in the WISE sample doesn't mean the 'failure of SETI to find anything', I'd be surprised if many ETI's actually englobed their whole galaxy in Dyson structures: As others have pointed out, unless there is a specific need for such an immense amount of energy and a unifying cause behind them, it seems like a waste of effort to englobe every star, and nature does not favour ruinous inefficiency. Plus it would disrupt the natural processes home galaxy considerably, and perhaps have negative consequences on future habitability.

eburacum45
2015-Apr-24, 01:11 PM
Here's an alternative to a galaxy englobed inside dyson spheres; a galaxy shrunk to the size of a globular cluster
http://www.orionsarm.com/eg-article/552d31f1832b6
actually these could probably be even smaller, but the rate of collisions would be higher.

publiusr
2015-Apr-25, 07:19 PM
And I really wanted to see a Dyson Mega-sphere too.

TheNewt
2015-May-01, 06:31 AM
Perhaps the universe is still too young for the development of civilizations that affect the entire galaxies in such a way they are viewed from many millions of light years away. Perhaps intelligent life has only shown up in the last few minutes in the cosmic clock? If intelligent life as capable of us or more advanced only started appearing in the last several million years, it should be no surprise no life was detected in 100,000 galaxies since we aren't observing what any of those galaxies look like currently.

But the issue with such idea is obvious- how is it that intelligent life could only show up recently? Calculations of when intelligent life first occurred vary highly due to the speculative nature of the subject (we only have one reference point- us, after all) and have turned up numbers like 5 Gya, making such hypothetical species around the age of sol.

swampyankee
2015-May-01, 03:30 PM
I find it hard to believe that Scientific American would allow "a team lead by" to stand uncorrected, in the lead paragraph no less. What is the world coming to?

This is what happens when you don't teach grammar in school.

danscope
2015-May-01, 08:18 PM
I found it most interesting and enlightening to describe a truly advanced civilization capable of controling their growth and
symbiotic relationship with their planet / planets that produces no waste or other associated "problems" in living with their environment. Now that is certainly the best sort of progress indeed.

Dan

Noclevername
2015-May-02, 02:49 AM
I found it most interesting and enlightening to describe a truly advanced civilization capable of controling their growth and
symbiotic relationship with their planet / planets that produces no waste or other associated "problems" in living with their environment. Now that is certainly the best sort of progress indeed.

Dan

It sounds great if you're a back-to-nature type. It also sounds like a society that can't communicate with us and is irrelevant to our detection methods.


relationship with their planet / planets
Planet, very much singular, as a technology like that can't provide any means of reaching space; leaving a gravity well is energy-intensive.

galacsi
2015-May-02, 07:25 AM
It sounds great if you're a back-to-nature type. No , not at all and this is the only future we have . These Dyson's spheres and karbatchev's stories mean absolutely nothing. They are sheer nonsense.Bad SF from the previous century.


It also sounds like a society that can't communicate with us and is irrelevant to our detection metho ds. Yes probably but because it is too much evolved and not not enough.

Planet, very much singular, as a technology like that can't provide any means of reaching space; leaving a gravity well is energy-intensive. Just a common prejudice.

Noclevername
2015-May-02, 07:38 AM
No , not at all and this is the only future we have .

It seems like an unlikely development. We will have more efficient technologies, but to have no industrial waste at all, you must have no industry. I can't see a mass reversion to hunting and gathering taking place.


These Dyson's spheres and karbatchev's stories mean absolutely nothing. They are sheer nonsense.Bad SF from the previous century.

Possibly, but it's not like all or nothing are the only options for technological development.

Yes probably but because it is too much evolved and not not enough.

Evolution is biological, it has nothing to do with technology level.

Just a common prejudice.
If you think so, then please explain how the physics of non-industrial space flight would work.

swampyankee
2015-May-02, 01:17 PM
Just FYI, I'm American and I don't use pavement to mean road. I use it simply to refer to a hardened surface that you walk on, so it could be a sidewalk or a road or a basement.

I agree with the point about language changes.

Not basement, at least not here. But, yes, the US usages with which I'm familiar all use "pavement" to indicate the stuff that covers the dirt, not the paved thing that cars drive on.

galacsi
2015-May-02, 05:51 PM
It seems like an unlikely development. We will have more efficient technologies, but to have no industrial waste at all, you must have no industry. I can't see a mass reversion to hunting and gathering taking place.

Hunting and gathering , sure ! ,it is like when you object to nuclear energy and so obviously you must go back to candles and torches for lighting your cave ! No waste industrial or else is not the real goal , I am sure Danscope means no unrecyclable waste.



Possibly, but it's not like all or nothing are the only options for technological development. Agreed


Evolution is biological, it has nothing to do with technology level. ? ? Evolution is a general concept you can apply on many things and why not for a society or a civilization ?


If you think so, then please explain how the physics of non-industrial space flight would work.One thing is sure , some very complex things have been done before the industrial age and the physical laws were the same as today and as they will be in the future. And the industrial way of doing things is not eternal , we did not reach the end of history , the future is open.

danscope
2015-May-02, 06:32 PM
Well said, Galacsi !

swampyankee
2015-May-02, 08:03 PM
A negative result is simply a negative result, especially as there are no real theories about abiogenesis, the evolution of multi-cellularity, or why intelligence evolved. This is unlike what happened with the Michelson-Morley experiments, where there was a specific theory that predicted a specific result, that was not found: this demonstrated that the ether didn't exist.

Noclevername
2015-May-03, 01:36 AM
Hunting and gathering , sure ! ,it is like when you object to nuclear energy and so obviously you must go back to candles and torches for lighting your cave ! No waste industrial or else is not the real goal , I am sure Danscope means no unrecyclable waste.


Agreed

? ? Evolution is a general concept you can apply on many things and why not for a society or a civilization ?

One thing is sure , some very complex things have been done before the industrial age and the physical laws were the same as today and as they will be in the future. And the industrial way of doing things is not eternal , we did not reach the end of history , the future is open.

So, if you have no concrete answers, you vague things up until you're arguing about stuff that's inarguable? Nice debating tactic. There's no shame in admitting you were wrong.

danscope
2015-May-03, 02:36 AM
The thing about the future is that we can and do influence it.

Noclevername
2015-May-03, 08:17 AM
The thing about the future is that we can and do influence it.

Agreed, though this thread isn't really about us or our future. It's about the attempt to detect the output signature of a certain kind of ET civilization, and the results of that attempt.

I think a Kardashev level 3 culture is unlikely-- there's no way that much energy could be gathered for nonlocal use, given lightspeed lag in transferring that energy. A single Dyson sphere might be built, but only if there were a specific task that required that much energy; and I can't think of anything that could be done that way, that could not be accomplished much more simply by other means.

Still, that doesn't mean we should not look for them. It's a relatively easy kind of assay, well within our current capabilities, and if it comes up negative we really haven't lost anything.

marsbug
2015-May-03, 11:12 PM
Normally I wouldn't bring up my own blog in relation to a discussion here, but I e-mailed Professor Wright from G-HAT and asked him a few questions, some of which are not a killion miles rempoved from the discussion here. The post I wrote as a result of the discussion is here (http://ancientsolarsystem.blogspot.co.uk/2015/05/q-and-with-professor-wright-of-g-hat.html). I hope I'm not stepping over any forum rules by putting this up - if so I'll copy and past the answers he gave (as long as he's ok with that when I ask him, and I think he would be) as I think this is definitely relevant to the discussion.

The professor seems to agree that a K3 civilisation is both an extreme case and only one potential route that even a power hungry and monolithic civilisation could take - but extremes do happen in nature, human governments have often authorised projects that simpler civilisations would see as examples of how natural resources can be tapped excessively and wastefully by an intelligence. His motivation for the search is simply that such an extreme course of action would be relatively easy to spot, and could not be ruled out even amongst 1 in 100,000 galaxies unless the small effort was made to actually look.

I wouldn't call the search a waste. Even though no evidence of a galaxy completely taken over by ravenous enrgy use was detected (which is something we should perhaps be grateful for) it has unearthed strange objects new to science, and also shown that massive galactic alteration of that kind by any ETI's that are out there is, at most, incredibly rare.

Jens
2015-May-04, 02:56 AM
The professor seems to agree that a K3 civilisation is both an extreme case and only one potential route that even a power hungry and monolithic civilisation could take - but extremes do happen in nature, human governments are examples of how natural resources can be tapped excessively and wastefully by an intelligence.

I don't see what is extreme about government. Humans are social creature and as such, we expend energy on things like improving our social ranking and getting other people to do what we want or to not do what we don't want. Governments seem to me a natural extension of that. K3 civilizations are unnatural however.

marsbug
2015-May-04, 08:56 AM
I've edited my previous post for clarity: Governments per se are not extreme, but some governments have authorised and/or permitted uses of natural resources that would seem extreme to less advanced civilisations. Imagine how an island tribe would view a major land reclamation project or hydro electric dam for example. Some governments simply build islands where they wish! The government is not meant to be an example of extrtemity, the resource use as seen through the eyes of a simpler people is.
I agree that a k3 civ seems unnatural. But extreme uses of natural resources do happen where it is in demand, and it's no great effort to look through our telescopes and check to be sure.

malaidas
2015-May-04, 10:49 PM
Not basement, at least not here. But, yes, the US usages with which I'm familiar all use "pavement" to indicate the stuff that covers the dirt, not the paved thing that cars drive on.

Fair enough as I said tis may be local dialect, or e en a misunderstanding on my brothers part. the basic principle behind what I was saying stands though.

swampyankee
2015-May-05, 02:10 AM
Fair enough as I said tis may be local dialect, or e en a misunderstanding on my brothers part. the basic principle behind what I was saying stands though.

I think it was Mencken who said that the US and Britain are two countries separated by a common language. Considering British accents, one wonders if Britain can be called one country separated by a common language. ;)

Pronunciation can be funny, too: when my brother lived in Ohio, the street's name was Worcester. In the Northeast, that's pronounced "Wooster." When my father drove out to visit him, the local he asked for directions was very confused until he looked at the car's license plates.

malaidas
2015-May-06, 07:20 AM
in that light yes, the dialectical differences in Britain are very wide over very short distances. Greater perhaps than across the entire US in a region smaller than most states.

Incidentally, that pronunciation of Worchester, would be the same as the 'correct' way to say it in British English as well.

Eta: and in this microcosm you can see the problems I refer to happening. For examplr, my wife's family are from Yorkshire and despite having been together 13 years there are still times when 1 or another of her relations say things that I struggle to understand and vice versa if I lapse into scouse. The thing is this is over a distance of just 90 miles.

Just for example, if I were to say 'me ed's chocka' few outside Liverpool would know what I meant, although in context you might be able to guess. Even if I wrote it down in proper syntax.

'My head is chocka' you would still need context to work out what I meant, which is 'I am unbelievably busy'. It's just common parlance round here.

It stems from chocked up, I.e. Over full. So basically you can't deal with anything more, and thus makes sense in context, but its specific to Merseyside And meaningless to anyone else. All this is before you get started on something like the word 'crack', which basically means something outside of work as an extremely crude definition, it's a word with many subtle nuances. But for instance if I said 'I had a good crack last night' most of the English speakers of the world would completely get the wrong end of the stick, thinking I was talking about a class A drug, when in fact it has nothing to do with such, it means 'I had a good time with good people'

The point of course coming back, but this is just over a short distance, over a short period. One can only imagine the problems over interstellar distances. It would be like someone speaking middle English within a few centuries.

swampyankee
2015-May-06, 09:55 AM
I remember people saying mass communication would homogenize English. Largely, it's not happening, possibly because people use language to communicate social status, like group membership, as much as more "useful" information.

malaidas
2015-May-06, 10:25 AM
Yep, this is the disconnect at work. We naturally form social groups as part of defining our own identity, and within such language evolves somewhat independently, the greater the separation between such groups and the greater the time period, the greater the independence and degree of such evolution.

malaidas
2015-May-06, 11:21 AM
in Conclusion here I shall leave you with a well known Barnsley adage

'If ever tha does ought for nought make sure tha does it for tha sen.'

This is the kind of thing I had to come to grips with. Now written you can probably pick out what it means, spoken it's a nightmare until you are clued up. For instance that Yorkshire never fully dropped their thees and thous. Just imagine if you will, hearing something like that spoken heavily accented, soft and fast. It was almost gibberish. I am clued in for the most part now but it's taken time and more than a little effort on my part.

Ps: translation if required:

'If ever you do something for nothing, make sure you do it for yourself'

Dave12308
2015-May-19, 09:21 PM
Though I was quick to point out that the lack of any totally dysonian galaxies in the WISE sample doesn't mean the 'failure of SETI to find anything', I'd be surprised if many ETI's actually englobed their whole galaxy in Dyson structures: As others have pointed out, unless there is a specific need for such an immense amount of energy and a unifying cause behind them, it seems like a waste of effort to englobe every star, and nature does not favour ruinous inefficiency. Plus it would disrupt the natural processes home galaxy considerably, and perhaps have negative consequences on future habitability.

On this planet, we always talk about how the INTELLIGENT thing to do for the future is to CONSERVE our natural resources and what nature provides us on the planet.

WHY would an ADVANCED INTELLIGENT species suddenly decide they need to harness and make use of their entire galaxy's resources? Basically Dyson is saying that an ADVANCED civilization would be MORE wasteful than we are.

I don't see this happening, so I don't see Dyson swarms as a "real" thing. It's just not practical.

marsbug
2015-May-19, 10:05 PM
You're right, it would be wasreful, reckless, and perhaps even self destructive over the long term. It would be a paradox: A highly intelligent entity acting irrationally, self destructively, and shortsightedly. Um. Not like us, the only high level intelligence we know of for sure, at all.....

John Mendenhall
2015-May-19, 10:07 PM
This is what happens when you don't teach grammar in school.

That's right. I always wanted to be a good grammarian and now I are one.

Noclevername
2015-May-19, 10:13 PM
On this planet, we always talk about how the INTELLIGENT thing to do for the future is to CONSERVE our natural resources and what nature provides us on the planet.

WHY would an ADVANCED INTELLIGENT species suddenly decide they need to harness and make use of their entire galaxy's resources? Basically Dyson is saying that an ADVANCED civilization would be MORE wasteful than we are.

I don't see this happening, so I don't see Dyson swarms as a "real" thing. It's just not practical.

I agree that Dyson spheres are not likely, but not for that reason.

You're thinking in terms of a planet-based society. A long term space-based society would consist entirely of planned, artificially maintained environments, and might not value natural ecologies to the same degree as planet-dwellers.

KABOOM
2015-May-20, 05:35 PM
Is "transcendence" required?

Assume that colonization on the galactic level can only be achieved via robotic, machine life ("self replicating probes", etc). Assume that biological life can not endure given the vast distances and hazards of getting there and then acclimating to any new worlds.

Now the above are "assumptions" but ones that I have frequently seen posited by advocates as to the potentiality of significant galactic colonization. Why bother?

Absent the heretofore untestable premise that man's mind can be uploaded and integrated into machine-life, to simply spend HUGE resources to build machines that will be programmed to expand, consume stellar resources and expand further would seem rather pointless, at least from the perspective of the biological life source that would have given rise to such an effort.

Noclevername
2015-May-21, 01:26 AM
Is "transcendence" required?

Assume that colonization on the galactic level can only be achieved via robotic, machine life ("self replicating probes", etc). Assume that biological life can not endure given the vast distances and hazards of getting there and then acclimating to any new worlds.

Now the above are "assumptions" but ones that I have frequently seen posited by advocates as to the potentiality of significant galactic colonization. Why bother?

Absent the heretofore untestable premise that man's mind can be uploaded and integrated into machine-life, to simply spend HUGE resources to build machines that will be programmed to expand, consume stellar resources and expand further would seem rather pointless, at least from the perspective of the biological life source that would have given rise to such an effort.

What factors are there about interstellar travel that would make biolife unable to survive it? What would make biological organisms unable to survive in star systems other than their own?

danscope
2015-May-21, 01:28 AM
You have to respect space as an hostile environment first.

Noclevername
2015-May-21, 01:36 AM
You have to respect space as an hostile environment first.

No kidding! No one's ever thought of that. :rolleyes:

Really though, if a civilization has even gotten close to the point where they can plan to travel the vast distances between stars, they would have to have long since established themselves in artificial environments in space. Otherwise they'd have no hope of surviving the trip at all, as opposed to merely having very slim hope of surviving the trip.

As for the whole "mind uploading" deal, even if it happens, the robo-minds would still be in competition with the billions of biologicals who prefer the old ways.

malaidas
2015-May-21, 08:59 AM
of course that is assuming that such robolife didn't wipe out the biologicals.

The thing is though that I still don't think this evidence means that much.

IsaacKuo
2015-May-21, 03:08 PM
Assume that colonization on the galactic level can only be achieved via robotic, machine life ("self replicating probes", etc). Assume that biological life can not endure given the vast distances and hazards of getting there and then acclimating to any new worlds.

Now the above are "assumptions" but ones that I have frequently seen posited by advocates as to the potentiality of significant galactic colonization. Why bother?

One of my favorite pet ideas is the idea of relatively dumb self replicating probes which are designed as a weapon to fight a specific enemy--maybe a specific species, or even a specific race, or other self replicating probes (which themselves may be specifically targeting the creators of these newer defensive probes).

Even if these self replicating probes are designed to fight some small "local" war, they could spread throughout a galaxy simply because they were never programmed with a limit. Or, perhaps, there was indeed a limiter feature, but it was only active when the creators were still alive.

My point is that it could basically just be a particularly long-lived side effect of some war. Kind of like how we have land mines just lying around from old conflicts, but these self replicating probes expand and grow.

A sophisticated reason to "bother" expanding throughout the galaxy is not required. It could be a lowly reason.

marsbug
2015-May-22, 11:14 AM
Perhaps there are alternatives we haven't considered. If rummage in my grab bag of pet sci-fi ideas; Dusty (or complex) plasmas have been shown to be capable of behaving like crystals, liquids, and (via computer simulations) even DNA strands. Perhaps 'they' are there above us right now, in the form of organised collections of complex plasma that they've designed to act as probes, computers, or even uploaded their consciousness to. Plasma formations can travel at enormous speeds (CME's can reach thousands of km a second), maybe we're looking at the behaviour of the solar systems plasma, magnetic and electric fields and seeing the real interstellar civilisations without realising it. Or pick another wild idea out of the hat - my point is that we cannot predict the evolution of a space faring civilisation with any accuracy, not from our sample size of one that is earth. All we can do is cross off any of the most obvious possibilities and keep an open mind.

Noclevername
2015-May-22, 02:25 PM
All we can do is cross off any of the most obvious possibilities and keep an open mind.

Well, that's what the OP was all about. They searched for K3 civilization not because they thought it was likely to exist, but because it would be very obvious and easy to search for. You have to cut your coat to fit the cloth you have.

marsbug
2015-May-22, 02:58 PM
:) i realise its a point thats already been made on this thread but. yeah. exactamundo

danscope
2015-May-23, 06:36 PM
Hi Galacsi, You are quite correct.

eburacum45
2015-May-23, 10:22 PM
WHY would an ADVANCED INTELLIGENT species suddenly decide they need to harness and make use of their entire galaxy's resources? Basically Dyson is saying that an ADVANCED civilization would be MORE wasteful than we are.
In our system we 'waste' all but one billionth of the energy emitted by the Sun. That is all the energy that the Earth intercepts. That is nine orders of magnitude more waste than anything we can achieve on Earth, A frugal-minded civilisation would surely wish to gather some or most of that wasted luminosity and put it to useful work.

malaidas
2015-May-23, 10:24 PM
Its not a question of some Dyson spheres though. It's a matter of them setting them up galaxy wide.

Noclevername
2015-May-23, 11:22 PM
Its not a question of some Dyson spheres though. It's a matter of them setting them up galaxy wide.

With a light lag of 100 thousand years between one end and the other. Transferring energy over this distance is just a tad impractical and inefficient.

swampyankee
2015-May-24, 01:16 PM
Leaving aside the energy transfer, is it even sensible to talk about galaxy-spanning civilizations?

malaidas
2015-May-24, 02:28 PM
Well it's possible but as I have stated my objections to such a concept from a practical standpoint. It does seem highly unlikely.

Noclevername
2015-May-24, 03:17 PM
Leaving aside the energy transfer, is it even sensible to talk about galaxy-spanning civilizations?

Without our even having spread to other parts of our Solar System yet, we can't really say if it could work for humans, or more accurately post-humans by the time we get even to the nearest star. For aliens? Who knows.

swampyankee
2015-May-25, 02:56 AM
Without our even having spread to other parts of our Solar System yet, we can't really say if it could work for humans, or more accurately post-humans by the time we get even to the nearest star. For aliens? Who knows.

Unitary empires have been maintained with longer communication lags than would exist in a Solar System-spanning civilization, so I've no doubt that a civilization to span 100 AU or so would be possible. For it to be a hundred millennia, I think we'd need something remarkably stagnant.

Noclevername
2015-May-25, 03:48 AM
Unitary empires have been maintained with longer communication lags than would exist in a Solar System-spanning civilization, so I've no doubt that a civilization to span 100 AU or so would be possible. For it to be a hundred millennia, I think we'd need something remarkably stagnant.

Or patient.

Noclevername
2015-May-25, 04:00 AM
A civilization need not be completely uniform. Look at Western Civilization; it consists of many different countries unified only by similar, not identical, cultures. A Galactic Civilization might be unified by some post-biological AIs, each star system going their merry way but with the machines, who think on different time scales, remembering and influencing each society.

I'm not saying it's at all likely, but it isn't impossible.

KABOOM
2015-May-26, 12:45 PM
What factors are there about interstellar travel that would make biolife unable to survive it? What would make biological organisms unable to survive in star systems other than their own?

Interstellar travel is purported to be extremely dangerous to multi-cellular biolife. Radiation, loss of bone density to a name of a few hazards while on a spaceship for hundreds of years. Earth biolife is customized to thrive on one place in the Milky Way, that being Earth. Surviving in an alternate star system on an actual planet would require a heretofore unreconciliable melding together of an alien biosphere with Earthly biolife.

So basically two hurdles that today can not be cleared - intelligent biolife surviving a multi-decade space journey and then said biolife adapting to a new, hostile biosphere - would be needed to occur to give rise to galactic expansion.

IsaacKuo
2015-May-26, 01:27 PM
Interstellar travel is purported to be extremely dangerous to multi-cellular biolife. Radiation, loss of bone density to a name of a few hazards while on a spaceship for hundreds of years. Earth biolife is customized to thrive on one place in the Milky Way, that being Earth. Surviving in an alternate star system on an actual planet would require a heretofore unreconciliable melding together of an alien biosphere with Earthly biolife.

So basically two hurdles that today can not be cleared - intelligent biolife surviving a multi-decade space journey and then said biolife adapting to a new, hostile biosphere - would be needed to occur to give rise to galactic expansion.

Earth conditions can be replicated in a space habitat, though. Ten tons per square meter of radiation shielding replicates the radiation shielding of Earth's environment and magnetic field at sea level, and this mass may serve double duty as long term emergency supplies and propellant. The resources of planetary bodies in the destination system can be used to build more space habitats replicating Earth's conditions, rather than trying to find a planetary body which is similar to Earth.

Hypothetical aliens? It's hard to say what they'll necessarily be like, but it's plausible for hypothetical aliens to have evolved on planets vaguely similar to Earth. If we're talking biological chemistry vaguely similar to what we're familiar with, we're talking liquid water pressure/temperature conditions. This means we're talking gravity levels that are at most a few times greater than Earth's--which is still readily replicated with spin gravity. The amount of radiation shielding required might be higher, if the hypothetical alien species evolved in a subsurface ocean environment many kilometers below an ice crust, but it might also be similar or less.

I have some fun pet ideas about hypothetical aliens living in extreme environments like Neptune, which would only be able to explore the universe by robotic proxy. But these speculations involve radically different biological chemistry than what we're familiar with (and we really don't have a good basis to expect such radically different biological chemistries could even work).

Spacedude
2015-May-26, 01:40 PM
Maybe Type 3 civilizations are not being detected because by the time they reach that extreme advanced stage of development their scientists have confirmed that our universe is just one of an infinite number of universes and have discovered a method to open doors to them. After exploring many of the other universes they have found at least one that is much less dangerous than ours so have moved there.

Noclevername
2015-May-26, 05:42 PM
Interstellar travel is purported to be extremely dangerous to multi-cellular biolife. Radiation, loss of bone density to a name of a few hazards while on a spaceship for hundreds of years. Earth biolife is customized to thrive on one place in the Milky Way, that being Earth. Surviving in an alternate star system on an actual planet would require a heretofore unreconciliable melding together of an alien biosphere with Earthly biolife.

So basically two hurdles that today can not be cleared - intelligent biolife surviving a multi-decade space journey and then said biolife adapting to a new, hostile biosphere - would be needed to occur to give rise to galactic expansion.
So, difficult but not impossible to overcome. And predictable, so any species with the capacity to actually build a starship would also know how to protect its passengers.

As for adapting to alien biospheres, if they've lived generations on a ship why would they need planets? Build your own biosphere to suit yourself.

Jens
2015-May-26, 11:29 PM
Unitary empires have been maintained with longer communication lags than would exist in a Solar System-spanning civilization, so I've no doubt that a civilization to span 100 AU or so would be possible. For it to be a hundred millennia, I think we'd need something remarkably stagnant.

It's an interesting point. I think it might have taken a clipper several months to travel from Great Britain to Australia or the Far East, so the communication lags would be on the order of up to a year perhaps. But I think the situation is somewhat different because in the 19th century, we had nation-states and the British essentially saw themselves as patriots competing with other people in a basically interdependent world. Earlier non-nation empires did have difficulty coping with the problem of communication and tended to split fairly quickly because of rivalries between powerful local leaders. There was also the fact that not only information but resources could be brought back with the same time lag, so there was an incentive to control those empires. Maintaining a colony on Mars wouldn't bring anything meaningful for an empire on earth except perhaps prestige.

Noclevername
2015-May-26, 11:34 PM
I think the trouble here is in defining "a civilization". Does it need to be a single government? Or can it mean a widespread group of cultures that share some common purposes?

malaidas
2015-May-27, 03:50 PM
This is indeed a huge problem but it goes further, even if they began with a common purpose, there is no reason to suggest that different disparate groups would maintain the same common purpose over generations.

Fiery Phoenix
2015-May-27, 04:22 PM
I think the trouble here is in defining "a civilization". Does it need to be a single government? Or can it mean a widespread group of cultures that share some common purposes?
On the cosmic scale, it's probably sufficient to think of 'civilization' as equivalent in meaning to the word race (e.g. the human race).

That being said, I do have a sneaking suspicion that if we ever make contact with an intelligent civilization, they will be far more 'united' than we are.

malaidas
2015-May-27, 04:33 PM
I disagree, not because they won't be more 'civilised' but simply because of separation times as I have said. Independent social evolution will lead almost certainly to very different values and culture etc in any species adaptable enough to have developed such a civilization in the first place.

Noclevername
2015-May-27, 04:33 PM
That being said, I do have a sneaking suspicion that if ever make contact with an intelligent civilization, they will be far more 'united' than we are.

Really? I think the opposite; If they can reach us, they will surely have spread throughout their own space, and have room for a great deal of variation and establishing independent communities. Remember, the ISS was built by many nations during the Cold War, when we were at our least unified, so maybe a more resource-rich species can cooperate on a starship.

What reason do you have for thinking they will be more unified than us?

malaidas
2015-May-27, 04:49 PM
Agreed. Ok we are basing stuff on a sample size of 1 but we can trace the way we are right back to how this was advantageous evolutionary, and how such details are an essential part of why homo sapiens has developed to have the potential to even consider such interstellar journeys in the distant future (whilst alive that is).

A society that doesn't naturally evolve over time will not be able to develop the science required in all probability, but such an ability will lead to disparate cultures over time as a natural result.

Fiery Phoenix
2015-May-27, 04:50 PM
Really? I think the opposite; If they can reach us, they will surely have spread throughout their own space, and have room for a great deal of variation and establishing independent communities. Remember, the ISS was built by many nations during the Cold War, when we were at our least unified, so maybe a more resource-rich species can cooperate on a starship.

What reason do you have for thinking they will be more unified than us?
This is admittedly a good point that I hadn't considered in my reasoning. Having said that, interstellar travel is an achievement that, in my opinion, can only be attained through collaborative effort. When I think of spacefaring alien civilizations, I tend to envision a civilization that is more unified and integrated than we ever will be, a civilization that has come to a complete understanding of its own intellectual and creative capabilities.

You're correct in thinking that colonizing space would lead to more segregation in the long run. But this probably boils down to how long the civilization in question has been enjoying space travel; the longer they have been 'out there', the more likely they will end up forming independent populations across the galaxy.

malaidas
2015-May-27, 05:47 PM
Precisely. So how long do you think it will take to colonize an entire galaxy such that the effect of Dyson spheres could've detected as suggested?

On a smaller scale the further such a civilization started from us, the longer they would have been out there in high probability. And there is of course a much greater likelihood of them starting out further rather than nearer.

Fiery Phoenix
2015-May-27, 06:11 PM
Personally, I don't see how Dyson spheres would work in practice. I believe Dyson's original proposition involved the use of artificial satellites (or some such) for building the sphere, but our current idea of Dyson spheres doesn't really sound like something that would actually be attainable in the real world.

IsaacKuo
2015-May-27, 06:55 PM
Personally, I don't see how Dyson spheres would work in practice. I believe Dyson's original proposition involved the use of artificial satellites (or some such) for building the sphere, but our current idea of Dyson spheres doesn't really sound like something that would actually be attainable in the real world.

For stars with a sufficiently high brightness compared to mass, statites can use photon pressure to hover in place. This is plausibly doable for sun-like stars, but perhaps not red dwarf stars.

Another concept for creating a Dyson shell is to produce the outward supporting force with something like maglev tracks--working against masses which are zooming along them at faster than orbital speed.

Fiery Phoenix
2015-May-27, 07:30 PM
I wonder why we aren't interested in looking for von Neumann robots/probes? Technological limitations? They honestly seem far more probable to find around the Galaxy than Dyson spheres to me (albeit far more difficult to detect with our current methods).

IsaacKuo
2015-May-27, 07:56 PM
I wonder why we aren't interested in looking for von Neumann robots/probes? Technological limitations? They honestly seem far more probable to find around the Galaxy than Dyson spheres to me (albeit far more difficult to detect with our current methods).

This is one of my favorite pet ideas. Unfortunately, it's extremely challenging to try and do. Obviously, you have to start with trying to figure out what you might be looking for. One idea I have come up with is the idea of "slow" VN probes which travel from star system to star system at around 100km/s to 1000km/s (suitable for free gravity slingshots). We might spot these as "interstellar comets", doing a close flyby of the Sun.

Unfortunately, doing a BOE calculation on the sensitivity of SOHO and STEREO showed me that such a probe would have to be quite large to be visible to them--maybe 300m in diameter before it's even a question of visibility. So, even though these are popularly used to hunt for sun grazing comets, an interstellar probe would just invisibly cruise right in front of them.

Another idea I had was trying to figure out where a VN probe might be located permanently within the Solar System, in order to make long term observations of Earth and other planetary bodies. Unfortunately, all the plausible locations I came up with were also hopelessly difficult for us to detect a probe.

malaidas
2015-May-27, 07:58 PM
In fact one has to look at this and see that the chances of us ever encountering or even finding evidence of alien intelligence are vanishingly slim, although never say never, and that this fact is actually irrelevant to the question of whether such exist. It doesn't mean stop looking but the question is unfalsifiable in practice. Given the sheer size of the universe makes it rather likely that there is one sonewhere, given the sheer size of universe makes it highly unlikely that we will ever answer the question.

Noclevername
2015-May-27, 09:18 PM
Personally, I don't see how Dyson spheres would work in practice. I believe Dyson's original proposition involved the use of artificial satellites (or some such) for building the sphere, but our current idea of Dyson spheres doesn't really sound like something that would actually be attainable in the real world.

The infrared signatures they attempted to find were based on energy usage and waste heat output, not physical structures. The signature would be the same for either kind.

Gomar
2015-May-28, 01:50 AM
Up till the mid-20th.c. most people on Earth lived with no TV, radio, computers, Internet, phones, cars, etc.
There were people living naked in the African and Asian and Amazon jungles with no tech or worries about what
stock went up or down.

Thus, explaining failure of SETI. Most alien civilizations are in the stone or jungle age; why should they fly to the Moon or Mars, or send E-mails, or take selfies, or browse the web, or send messages into space hoping 50k from now someone will get it, instead of chillin' at the beach all day long?

Noclevername
2015-May-28, 02:01 AM
Distance explains the lack of signals quite nicely. The universe is huge.

Fiery Phoenix
2015-May-28, 02:11 PM
The infrared signatures they attempted to find were based on energy usage and waste heat output, not physical structures. The signature would be the same for either kind.
I wasn't specifically referring to the article in my comment, but you're right.

publiusr
2015-May-30, 06:44 PM
I wonder how big a civilization has to get to look like a cold spot...