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View Full Version : The Fermi Paradox, Self-Replicating Probes, & Interstellar Transportation Bandwidth



A.DIM
2011-Nov-29, 03:52 PM
Here's an interesting paper from arxiv (http://arxiv.org/PS_cache/arxiv/pdf/1111/1111.6131v1.pdf) suggesting SRPs in our solar system might well be awaiting our discovery, and that lack of serious consideration for such self replicating probes has left a gap in our SETI investigations. I'd have to concur.

iquestor
2011-Nov-29, 07:09 PM
A Very interesting paper. Not sure I agree with searching for ET in other Galaxies though. Like the idea of searching for SRP's in the solar system which seems somewhat plausible.

transreality
2011-Nov-29, 09:48 PM
If an alien space ship capable of travelling here, reproducing itself, and then refuelling the copy and travelling on, by any conceivable mechanical method surely we'd notice the environmental impact. The construction infrastructure made by the replicating probe would remain, or the mined out moon we would have noticed. Otherwise the machine would have to be unnecessarily efficient. If such a device arrived now, and starting to trying to replicate itself it would represent an obvious industrial project on a scale beyond that which we are capable.

such a self-replicating probe strategy may be effectively similar a berserker strategy... does the probe ask permission to start exploiting the resources of an alien solar system?

R.A.F.
2011-Nov-30, 12:12 AM
...that lack of serious consideration for such self replicating probes has left a gap in our SETI investigations.

...only if you assume that these probes actually exist. If not, no "gap".

R.A.F.
2011-Nov-30, 12:15 AM
If an alien space ship capable of travelling here, reproducing itself, and then refuelling the copy and travelling on, by any conceivable mechanical method surely we'd notice the environmental impact.

Naw....these "probes" are all "sneaky" and stuff. :)

iquestor
2011-Nov-30, 03:24 AM
If an alien space ship capable of travelling here, reproducing itself, and then refuelling the copy and travelling on, by any conceivable mechanical method surely we'd notice the environmental impact. The construction infrastructure made by the replicating probe would remain, or the mined out moon we would have noticed. Otherwise the machine would have to be unnecessarily efficient. If such a device arrived now, and starting to trying to replicate itself it would represent an obvious industrial project on a scale beyond that which we are capable.

such a self-replicating probe strategy may be effectively similar a berserker strategy... does the probe ask permission to start exploiting the resources of an alien solar system?

I think you are assuming said SRP would do things on a large scale and make zillions of copies, however I don't think this is a foregone conclusion. I think its plausible that the probe could make say a hundred copies of itself from asteroid material and we would never ever notice, then send off 90 of its copies to the next star systems. The remaining 10 could then just recon the system for things that would be interesting to the makers, say life habitats or something. I dont think we would notice them unless they were programmed to become noticed.

eburacum45
2011-Nov-30, 06:12 AM
Presumably a SRP would not only collect information, but also send that information back to its originating system, wherever that may be. Perhaps the most obvious signature of a SR in our system would be the transmitter it would build to send this data back, and possibly the receiver it would build to recieve new orders. On the other hand if the home system is transmitting new orders, then we might have a chance of intercepting the inwards transmission ourselves.

A.DIM
2011-Nov-30, 02:43 PM
A Very interesting paper. Not sure I agree with searching for ET in other Galaxies though. Like the idea of searching for SRP's in the solar system which seems somewhat plausible.

Heh, I agree.
SETI conducts its searches at galactic distances; Perhaps it should be listening closer to home.
:D

A.DIM
2011-Nov-30, 02:48 PM
If an alien space ship capable of travelling here, reproducing itself, and then refuelling the copy and travelling on, by any conceivable mechanical method surely we'd notice the environmental impact. The construction infrastructure made by the replicating probe would remain, or the mined out moon we would have noticed. Otherwise the machine would have to be unnecessarily efficient. If such a device arrived now, and starting to trying to replicate itself it would represent an obvious industrial project on a scale beyond that which we are capable.

I suspect any ETi capable of sending out SRPs is thousands and more years beyond what we’re capable of, let alone what we might conceive.
I can agree though, it seems we might’ve discovered something about them, if not the probes themselves (or eburacum’s transmitters/receivers), even while I don’t think we’ve come close to thoroughly exploring our own system.
But as Wiley points out: ”When we populate the equation with the lower and upper estimates, it yields Nr = 10^2–10^11 SRPs in our solar system at this very moment. The absurdity of this result underlies the tremendous burden of the Fermi Paradox and demonstrates why many ETI-hopefuls have shied away from even the remotest consideration of SRPs.”
That’s a lot of probes we’ve yet to discover!


such a self-replicating probe strategy may be effectively similar a berserker strategy... does the probe ask permission to start exploiting the resources of an alien solar system?

Yes, Wiley discusses the “voluntary refrainment” argument and berserkers potential, but counters it with the “worldwide undetected-uncorrected-RAM-bit-error rate (being) negligible,” which shows our machines by and large do what we program them to do. Is there something what precludes some advanced ETi from achieving such engineering and data integrity? I wouldn’t think so.

IsaacKuo
2011-Nov-30, 03:13 PM
Thanks for the link to this paper. I need to write a similar paper to model the effects of competing war machines--all originating from the same place in the galaxy, on the assumption that they're primarily designed by competing factions of the same species.

The discussion of potential predator-prey relationships is fun speculation, but I find it more plausible for machines to be specifically designed to destroy others rather than to spontaneously mutate into predators.

R.A.F.
2011-Nov-30, 05:16 PM
SETI conducts its searches at galactic distances...

Please cite the SETI page where it talks of searches in other galaxies.


Perhaps it should be listening closer to home.

Please present your reasoning to believe that SETI is not listening closer than galactic distances.

transreality
2011-Nov-30, 09:49 PM
Presumably a SRP would not only collect information, but also send that information back to its originating system, wherever that may be. Perhaps the most obvious signature of a SR in our system would be the transmitter it would build to send this data back, and possibly the receiver it would build to recieve new orders. On the other hand if the home system is transmitting new orders, then we might have a chance of intercepting the inwards transmission ourselves.

Thats a good point, if even a hundred were being built per visited star then every star would have multiple transmitters sending data home; surely something would show up on SETI searches.

antoniseb
2011-Nov-30, 10:56 PM
... surely something would show up ...
I'd go with "maybe something would show up". If the probes are nanotech, and the signals are highly directional (i.e. laser) packets sent once in a while from a KBO or Neptune trojan, how would we see it?

R.A.F.
2011-Nov-30, 11:18 PM
Maybe the probes are invisible, and that's why we don't see them. :)

A.DIM
2011-Dec-01, 01:56 PM
Please cite the SETI page where it talks of searches in other galaxies.

Please present your reasoning to believe that SETI is not listening closer than galactic distances.

Although I think anyone who read the paper understood what I was saying, apologies it wasn’t clear to you. Divided into ranges of distance -solar system, Milky Way, Universe- SETI searches are listening primarily at galactic distances, limited to the MW. By and large they’re not listening for things within our solar system, nor are they listening for extragalactic sources (though a few have).
The “Search Archive” at the SETI institute gives every search conducted since 1960, providing resolution, frequency and objects searched. By this, I think there’s good reason to think SETI searches within our solar system (closer to home) are near nonexistent.

Ilya
2011-Dec-01, 03:12 PM
If an alien space ship capable of travelling here, reproducing itself, and then refuelling the copy and travelling on, by any conceivable mechanical method surely we'd notice the environmental impact. The construction infrastructure made by the replicating probe would remain, or the mined out moon we would have noticed. Otherwise the machine would have to be unnecessarily efficient. If such a device arrived now, and starting to trying to replicate itself it would represent an obvious industrial project on a scale beyond that which we are capable.
I am not at all sure we would recognize a "mined out moon" for what it is. There are many moons in the Solar System with features we simply cannot explain, but natural assumption in the minds of planetary scientists is to come up with "natural" theories.

Does this look mined out to you?

http://www.nasa.gov/images/content/168177main_image_feature_749_ys_4.jpg

A.DIM
2011-Dec-01, 03:21 PM
I am not at all sure we would recognize a "mined out moon" for what it is. There are many moons in the Solar System with features we simply cannot explain, but natural assumption in the minds of planetary scientists is to come up with "natural" theories.

Does this look mined out to you?

http://www.nasa.gov/images/content/168177main_image_feature_749_ys_4.jpg

It most certainly does.
Good point.

R.A.F.
2011-Dec-01, 03:31 PM
Although I think anyone who read the paper understood what I was saying, apologies it wasn’t clear to you.

Why that is about the most "polite" insult I have ever received. :)


I think there’s good reason to think SETI searches within our solar system (closer to home) are near nonexistent.

Why would SETI (which is primarily a radio search) search within our Solar System?...what would they search "for"?...and if they are not searching for radio transmissions, then by what method would this search within the SS be conducted?

R.A.F.
2011-Dec-01, 03:39 PM
Does this look mined out to you?

No, it looks like it has been bombarded over billions of years.


It is a shame we don't "do" science by how something looks, but by evidence...

IsaacKuo
2011-Dec-01, 03:42 PM
If an alien space ship capable of travelling here, reproducing itself, and then refuelling the copy and travelling on, by any conceivable mechanical method surely we'd notice the environmental impact. The construction infrastructure made by the replicating probe would remain, or the mined out moon we would have noticed. Otherwise the machine would have to be unnecessarily efficient.

Along with Ilya's note, it's also not clear that a machine leaving no traces would be unnecessarily efficient. Two potential uses for arbitrary "waste" matter are reaction mass and impact/radiation shielding. Because the exact content of the matter used is not important, what would otherwise be waste matter is actually useful.

As a result, the most natural thing could be to consume an entire comet/moon/asteroid, leaving nothing behind. It's not unnecessarily efficient to use "waste" matter for reaction mass. Putting it into the exhaust stream increases drive performance and efficiency compared to dumping it overboard or leaving it behind.

A.DIM
2011-Dec-02, 02:25 PM
Why that is about the most "polite" insult I have ever received. :)

Why should you be insulted? You didn't read the paper, did you?


Why would SETI (which is primarily a radio search) search within our Solar System?...what would they search "for"?...and if they are not searching for radio transmissions, then by what method would this search within the SS be conducted?

SETI is the search for extraterrestrial intelligence. It should not be limited to radio from faraway places. I expect by now, you know the almost nil odds for detecting ETi by radio transmission. And as the paper in question discusses, there's good reason to consider SRPs as plausible alternative. SETI should consider other possibilities and methods for research.

transreality
2011-Dec-02, 10:07 PM
Along with Ilya's note, it's also not clear that a machine leaving no traces would be unnecessarily efficient. Two potential uses for arbitrary "waste" matter are reaction mass and impact/radiation shielding. Because the exact content of the matter used is not important, what would otherwise be waste matter is actually useful.

As a result, the most natural thing could be to consume an entire comet/moon/asteroid, leaving nothing behind. It's not unnecessarily efficient to use "waste" matter for reaction mass. Putting it into the exhaust stream increases drive performance and efficiency compared to dumping it overboard or leaving it behind.

Most natural is to efficiently extract the precious elements and leave the rest in an expanding debris cloud, some of which may land on various potentially or actually inhabited worlds of the system. Why would they hoover up all the left over dust and carry the junk around the galaxy with them, it all requires fuel to move. Carrying inert matter and dumping in the exhaust stream; i'm not sure that works not even considering the cost of collecting it, and a self-replicating probe could repair itself faster that the incoming cosmic ray damage so carrying a massive shield of arbitary size made of indigestible dust doesn't seem useful.

the only reason to be 100% efficient is be conveniently invisible to the locals forever.

IsaacKuo
2011-Dec-02, 10:44 PM
Most natural is to efficiently extract the precious elements and leave the rest in an expanding debris cloud, some of which may land on various potentially or actually inhabited worlds of the system. Why would they hoover up all the left over dust and carry the junk around the galaxy with them, it all requires fuel to move.
Because they hoover up all the left over dust and don't carry it all with them. Instead, they use it mostly for reaction mass.

Anyway, a debris cloud would not last very long. Sunlight pressure would eliminate it on short timescales.

And so what if there are random pieces of larger waste debris, which are big enough to survive Earth's atmosphere? How would it look any different from any other meteorite? It's just waste matter.

Carrying inert matter and dumping in the exhaust stream; i'm not sure that works not even considering the cost of collecting it,
It works great. The marginal cost of collecting waste material is almost nothing, since you needed to sift through it to get at the "good stuff" anyway. The energy and power requirements for propulsion go down proportionately with the reaction mass used, so the more mass the better.

and a self-replicating probe could repair itself faster that the incoming cosmic ray damage so carrying a massive shield of arbitary size made of indigestible dust doesn't seem useful.
A self replicating probe may not necessarily have any self repair capability. It may be simpler and safer to simply self-terminate on errors to eliminate the possibility of mutation. After all, the good copies can recycle self-terminated probes into fresh copies.

Either way, self repair or replacement only work when power is available. When trekking across interstellar space, there's no solar power. A reasonable solution could be to shut down all systems during the journey, and to only revive when sunlight at the destination system thaws the probes out of hibernation mode.

R.A.F.
2011-Dec-02, 10:58 PM
Why should you be insulted?

Just because someone doesn't agree with you doesn't mean they don't understand...the implication that it must be "my fault" is rather insulting...


SETI is the search for extraterrestrial intelligence. It should not be limited to radio from faraway places.

I'm sorry, but that's not your "call" to make.


I expect by now, you know the almost nil odds for detecting ETi by radio transmission.

I don't play odds.


...as the paper in question discusses, there's good reason to consider SRPs as plausible alternative.

There's no reason to think that...wishful thinking does not qualify as evidence.


SETI should consider other possibilities and methods for research.

Like what?? Investigating flying saucer stories?...crop circles?...imaginary probes?


What SETI does is a proper scientific investigation...what you propose is not...

A.DIM
2011-Dec-03, 01:57 AM
Just because someone doesn't agree with you doesn't mean they don't understand...the implication that it must be "my fault" is rather insulting...

It's not a matter of you not agreeing with me, rather it's that you didn't read the paper (you obviously didn't answer that question for a reason) and thus didn't understand what I was saying. Who's fault should it be?
Frankly, I'm insulted every time you post in one of my threads when clearly you don't read the material I present.

Otherwise, we might get more insightful posts from you than ....



I'm sorry, but that's not your "call" to make.

I don't play odds.

There's no reason to think that...wishful thinking does not qualify as evidence.

Like what?? Investigating flying saucer stories?...crop circles?...imaginary probes?

What SETI does is a proper scientific investigation...what you propose is not...

eburacum45
2011-Dec-03, 08:21 AM
Well, I have read the paper, and perhaps the most interesting concept in it is that of the Interstellar Transportation Bandwidth. They suggest that individual colonies will be insulated from each other by the high cost of interstellar transportation, so that a colony which experiences high population pressure or resource depletion would not be able to export its problems to the next system, and so cannot cause a population explosion throughout the galaxy. This is an optimistic view, and allows a galaxy to have a number of moderately successful and sustainable colonies, even if some of those colonies individually experience high population growth and resource depletion.

I'm not entirely sure that the interstellar transportation bandswidth is quite as low as they calculate, however; a solar system which dedicated all available mass and energy to sending colonists to neighboring systems could flood those systems with arriving spacecraft. Wiley suggests that incoming colonists would probably be welcomed, for humanitarian reasons at the very least, after their long and arduous voyage. I suspect that there would be considerable amounts of data traffic too, sentient programs beaming themselves from star to star looking to increase the amount of available processing power.

Perhaps the inhabitants of a small, comfortable, sustainable colony might find themselves bombarded by colonists arriving in beam-propelled ships, and by artificial mind programs looking for substrates to run on. These small, easily sustainable colonies might not remain cosy backwaters for very long if their neighbors are densely populated and highly expansive.

Paul Wally
2011-Dec-03, 10:24 AM
I suspect that there would be considerable amounts of data traffic too, sentient programs beaming themselves from star to star looking to increase the amount of available processing power.



Interesting concept. I'm just thinking that there will have to be some kind of universal computer/ information processing protocol, but what would that be?

Tuckerfan
2011-Dec-03, 10:28 AM
Why the assumption that if probes are in our system, they'll be easy to identify and find? First and foremost, if you're worried about more primitive societies finding your probe and getting all freaked out about it, then you're going to want your probes to be very hard to detect. Given that we're now discovering that Star Trek like cloaking technology might be possible, any society which is 100+ more years advanced than we are, is going to be much better at hiding their stuff than we are at finding it. This desire to hide the probes is even greater if, like Hawking, you assume that there's a good chance you'll run into a hostile species. The last thing you want to do is give them a hint as to what your technology is like.

Then there's our ability to identify advanced technology were we to see it. What will a radio transmitter look like 100 years from now? It would be interesting to ask Edison, Marconi, and Tesla in 1911 what they thought radios would look like in 2011. I doubt if any of them could imagine a radio unit as small as that which fits in a typical smartphone, nor do I think that they could even guess at the capabilities of what a smartphone could do. If Kurtzweil's estimates of what technology will be like in 100 years are right, then our ability to predict, and thus identify, alien technology is going to be pretty limited.

Finally, there's a design aesthetic which goes into everything at a basic level, so deeply entwined with who we are as a species that it could make recognizing elements of alien technology difficult for us. We tend to prefer certain shapes at certain ratios for our designs, aliens may not necessarily prefer those same shapes or ratios.

R.A.F.
2011-Dec-03, 05:31 PM
...rather it's that you didn't read the paper (you obviously didn't answer that question for a reason) and thus didn't understand what I was saying. Who's fault should it be?

Of course I read the paper...man you are becoming so predictable...


...I'm insulted every time you post in one of my threads when clearly you don't read the material I present.

"Clearly?"...because my opinion is to disagree with what a paper says, I MUST NOT HAVE READ IT?


...we might get more insightful posts from you than ....


Everyone take notice...this is the "thanks" I get for agreeing with A.DIM...I shouldn't have gone against my nature, and simply have disagreed...



...and if it wasn't obvious, I am so out of this thread...

Extrasolar
2011-Dec-03, 06:20 PM
Seems to me there are far better ways to look for intelligent life than looking for probes that could be any size at any place in any number that may or not be trying to purposefully disguise themselves. Using a very limited range of measure to look at a whole has never stopped SETI though. I would imagine their results would mirror those results from current extremely limited searches.

A.DIM
2011-Dec-04, 10:10 PM
Of course I read the paper...man you are becoming so predictable...

"Clearly?"...because my opinion is to disagree with what a paper says, I MUST NOT HAVE READ IT?

:rolleyes:
This whole quibble originates with your statement:
“Please cite the SETI page where it talks of searches in other galaxies.”
Now, had you read the paper you’d have understood what I said about SETI listening only at “galactic” distances...
Yes, RAF, it seems rather clear.

So what is it you’re disagreeing with exactly, the ranges of distance as given in the paper?



Everyone take notice...this is the "thanks" I get for agreeing with A.DIM...I shouldn't have gone against my nature, and simply have disagreed...

Eh? You want “thanks” for agreeing with me in some other thread, even while your nature is admittedly disagreeable?
:boohoo:


...and if it wasn't obvious, I am so out of this thread...

Thanks!

whimsyfree
2011-Dec-05, 11:21 PM
Well, I have read the paper, and perhaps the most interesting concept in it is that of the Interstellar Transportation Bandwidth. They suggest that individual colonies will be insulated from each other by the high cost of interstellar transportation, so that a colony which experiences high population pressure or resource depletion would not be able to export its problems to the next system, and so cannot cause a population explosion throughout the galaxy. This is an optimistic view,

It seems realistic to me. The idea of galactic empires based on the mass movement of raw materials and living beings between different stars has always been an absurd projection of 19th century history into outer space.


a solar system which dedicated all available mass and energy to sending colonists to neighboring systems could flood those systems with arriving spacecraft

If they're suffering "resource depletion" and "high population pressure" how/why would they "flood" other systems with spacecraft? If you short of resources you don't spend up big on luxury projects like spacecraft. Do you really think the most economic way of dealing with an excessive population or lack of resources is to "dedicate all available mass and energy" to building giant spaceships? who would use the spaceships? Presumably aliens need to eat too. The mass starvation that would result after diverting all resources to the leaders' pet spaceship program might solve the high population pressure part of the problem, I suppose.

KeithW
2011-Dec-06, 02:12 AM
If they're suffering "resource depletion" and "high population pressure" how/why would they "flood" other systems with spacecraft? If you short of resources you don't spend up big on luxury projects like spacecraft. Do you really think the most economic way of dealing with an excessive population or lack of resources is to "dedicate all available mass and energy" to building giant spaceships? who would use the spaceships? Presumably aliens need to eat too. The mass starvation that would result after diverting all resources to the leaders' pet spaceship program might solve the high population pressure part of the problem, I suppose.

I'm the author of the paper in question. I specifically address the suggestion you make above. I refer to the idea that not only may there be a fairly strict limitation on transportation in general (in good times) but that in particularly bad times the interstellar transportation bandwidth (ITB) may nose-dive as a society undergoes collapse, thus preventing it from desperately reaching out at the last second. While the primary theory is the "ITB theory", I call this second theory the "canoe theory" in the paper because it reflects Easter Island's history: they not only destroyed their own society through deforestation but furthermore, they prevented their own escape by destroying their ability to construct the kinds of canoes they had used to reach Easter Island in the first place. Thus, due to the tremendous expense of long-distance travel which is only supportable in times of prosperity, the ITB might, in times of poverty, drop practically to zero.

Thanks for your thoughts.

Cheers!

http://keithwiley.com

Van Rijn
2011-Dec-06, 09:49 AM
I'm the author of the paper in question.


Welcome. It's an interesting article.



Thus, due to the tremendous expense of long-distance travel which is only supportable in times of prosperity, the ITB might, in times of poverty, drop practically to zero.


Yes, that's an important point. Economics is an issue that often seems to be ignored in discussions in this area. Interstellar flight is radically different from interplanetary flight and barring new physics appears to be very expensive in resources. Even without poverty, opportunity cost would still limit interstellar colonization. For example, if the parent civilization can build a starship to send a thousand people to another star, it almost certainly would be much cheaper to build a habitat for a thousand people that remains in the same system. Further, because it remains, it may be able to interact with the rest of the interplanetary civilization and provide economic return. A starship would be an economic drain without reward to the parent civilization.

eburacum45
2011-Dec-06, 09:52 AM
Hi Keith!

Your paper is certainly interesting. The concept of interstellar transportation bandwidth is a very useful one.
But as I suggested earlier, the amount of resources available in a solar system are very large indeed, and could be used to send very large numbers of spacecraft to nearby systems.
In particular a Sun-like star puts out 4 x 10e26 Joules per second, enough to power millions of starships a year.

Certainly this flow of transportation would be very small compared to the possible population of a densely populated system (which could easily be in the quadrillions) but even if a densely populated system only sends a few billion colonists to each of its neighbours those few billions of arrivals could overwhelm a smaller colony.

whimsyfree
2011-Dec-06, 10:00 AM
I'm the author of the paper in question. I specifically address the suggestion you make above. I refer to the idea that not only may there be a fairly strict limitation on transportation in general (in good times) but that in particularly bad times the interstellar transportation bandwidth (ITB) may nose-dive as a society undergoes collapse, thus preventing it from desperately reaching out at the last second. While the primary theory is the "ITB theory", I call this second theory the "canoe theory" in the paper because it reflects Easter Island's history: they not only destroyed their own society through deforestation but furthermore, they prevented their own escape by destroying their ability to construct the kinds of canoes they had used to reach Easter Island in the first place. Thus, due to the tremendous expense of long-distance travel which is only supportable in times of prosperity, the ITB might, in times of poverty, drop practically to zero.


It is a rare and good thing to have the author of a paper here to discuss it. You wont get much argument from me though. I am extremely skeptical of the concept of interstellar mass migration under any circumstances. To me the natural conclusion to draw from the complete lack of evidence for alien probes, alien signals, or alien "space miracles" (Dyson spheres etc) is that aliens, at least those capable of producing such things, are very rare. I'm very much in the minority here.

eburacum45
2011-Dec-06, 10:15 AM
To me the natural conclusion to draw from the complete lack of evidence for alien probes, alien signals, or alien "space miracles" (Dyson spheres etc) is that aliens, at least those capable of producing such things, are very rare. I'm very much in the minority here.Not at all; I largely share your opinion. But the window is certainly open for other possibilities.

Van Rijn
2011-Dec-06, 10:52 AM
To me the natural conclusion to draw from the complete lack of evidence for alien probes, alien signals, or alien "space miracles" (Dyson spheres etc) is that aliens, at least those capable of producing such things, are very rare. I'm very much in the minority here.

Eh? Could you describe what exactly you think your minority position is? I don't think many here would disagree that Dyson sphere building ETs must be rare. After all, where are the Dyson spheres? Given the lack of evidence, most here are skeptical about ETs in general, and extremely skeptical of ET visitation claims.

IsaacKuo
2011-Dec-06, 04:13 PM
Economics is an issue that often seems to be ignored in discussions in this area. Interstellar flight is radically different from interplanetary flight and barring new physics appears to be very expensive in resources. Even without poverty, opportunity cost would still limit interstellar colonization.

This depends heavily on where you are and what timescales are acceptable. Interstellar flight is similar to interplanetary flight in star clusters, where you simply wait for other star systems to pass nearby. Even fast relativistic transport can be relatively cheap from a black hole or neutron star system. But in either case, it would seem to make far more sense to colonize other juicy star systems than undesirable ones like our own Solar System.

The issue I see ignored almost all of the time is interaction of territorial factions with each other--especially ones which branch off from the same parent civilization. Branching off is a plausible situation where the competing factions are technologically on par with each other. For example, the branch factions may be dumb self replicating war machines designed to destroy each other.

If this scenario is considered at all, it's usually from the perspective of Cold War MAD thinking. The idea is that nukes make war impossible--you warmongers had better learn to end all war or else we will all go extinct and that'll show you! But this idealistic notion is either a fluke or just an illusion that never actually was. If you look at human history, warfare and colonial expansion have always been possible at the same time (and very often they go hand in hand).

If there are three or more factions competing with each other, then you would plausibly end up with a patchwork of occupied regions, with DMZs between them. There's a strong incentive to not initiate a border conflict, because this leaves that faction weak and vulnerable to the faction(s) on the other border(s). It makes more sense to husband one's forces in a defensive posture, and only react to invasions.

In human history, this sort of stalemate tends to break down because different factions tend to make alliances of convenience. This tends to produce two rival blocs. With only two blocs, one or both will eventually believe themselves to have the upper hand, and the result is war. Or someone will make a mistake and war results from escalation. Or both. In any case, the stabilizing effect of 3+ factions evaporates.

But dumb war machines designed to fight each other might be perfect game theory actors--unable to even conceive of forming an alliance of convenience. Or the aliens might have different psychologies and/or cultures which make the factions inherently distrustful of each other. Or maybe the aliens are simply smarter than humans, and have a better idea of the inherent risks of the two bloc system.

In any case, I'd like to see more study about the consequences of 3+ faction dynamics.

KeithW
2011-Dec-06, 06:05 PM
the amount of resources available in a solar system are very large indeed, and could be used to send very large numbers of spacecraft to nearby systems. In particular a Sun-like star puts out 4 x 10e26 Joules per second, enough to power millions of starships a year.

Certainly this flow of transportation would be very small compared to the possible population of a densely populated system (which could easily be in the quadrillions) but even if a densely populated system only sends a few billion colonists to each of its neighbors those few billions of arrivals could overwhelm a smaller colony.

You're correct of course. I think there are two points to be made here though. First, as I show in the paper, a useful calculation of the ITB should take into account several factors. You correctly demonstrate that the energy provided by a star is tremendous, but there are other conceivable limitations to the ITB. To a minor extent the availability of material for the construction and fueling of starships is a limitation. While energy and matter are theoretically one and the same, performing the necessary conversion at the atomic level (that is, replenishing potentially rare elements through solar-energy-to-matter conversion) is a hairy business. I'm confident it can be done, but an ITB calculation needs to take that sort of thing into account. The point of this line of reasoning isn't that the ITB is necessarily limited by materials instead of energy. The point is that an analysis based purely on the solar energy reserves of the host star is incomplete when attempting to calculate the ITB.

Also, the ITB is a rate, not a total. We need to calculate the rate at which starships can be constructed, fueled, populated, and shipped. That is, of course, a more difficult calculation than the mere energy reserves of the star because it must account for mining, refinement, construction, fuel-harvesting, etc. etc. It's a thorny calculation and I wholly admit that in the paper I only offer the roughest notion of how a genuine ITB would be calculated; I'm just trying to get the concept off the ground.

Another crucial point, which leads to my next point, is that economic factors are relevant. Theoretically, a large enough civilization can harness the power of a star. This is a Kardashev-II civilization. This is a huge economic scale however, and therefore is certainly relevant when calculating the ITB. For example, we, as not even a K-I civilization yet, cannot hope to use all that energy, due to our economic and technological youth. Therefore, our ITB limitation is not our star's energy output, but rather, our society's economic capability.

The third, and final point, is that we need to consider the timelines for these potential scenarios. It is true that a K-II civilization could conceivably achieve a tremendous ITB, but such a civilization will most likely have already spanned a vast interstellar neighborhood, so the ITB must necessarily be thinned across all potentially visitable worlds (the ITB estimate in the paper takes into account the number of neighboring societies). This dilutes the ITB to any one world of course. Furthermore, your final point above is of relevance here. While a K-II civilization may achieve a very high ITB, its neighboring societies may very well be far-advanced too, potentially approaching K-II themselves. I argue in the paper that the societal cost of unwelcome colonists (when considering the spread of societal pressures such as population density and resource utilization) is not a flat number but rather a ratio. It isn't that 100 colonists per year is low and 100,000,000 colonists per year is high. That is the wrong approach. Rather, it is the ratio of a society's population (or GDP in effect) to that inflowing colonist population and economic or related support cost. Perhaps a K-II homeworld can deliver billions of colonists per year, but if the neighboring societies are home to populations in the quadrillions, then the proportional impact is no worse that an earlier timeline scenario in which 100 colonists are delivered to a colony that is home to, perhaps, billions of individuals. Proportionally, it's the same thing. You seem to anticipate this argument when you argue that the homeworld may be enormous and the colonies may be very small. If that is true, then you are right and homeworld strife can kill a neighbor. I'm just not sure I buy it. By the time the homeworld is nearing K-II status, the adjacent colonies will be very old and well-established, and they will have propagated multiple generations of subsequent outward waves of continued colonization (as I said, a K-II homeworld implies a vast interstellar collective already in place). I'm not convinced that a homeworld capable of delivering billions of colonists per year will not be neighbor to colonies which are themselves population in trillions or beyond.

I hope a few researchers pick up my idea and attempt really thorough ITB calculations which take all of these ideas into account in one over-arching equation...that would just be awesome.

Cheers!

IsaacKuo
2011-Dec-06, 07:35 PM
The general impossibility or inefficiency of mass-energy conversion actually argues in favor of massive interstellar transport capability. Sunlight provides an incredible amount of energy, but there's relatively little capacity to store this energy within a single star system. There's a very limited amount of matter, and most of this is in the form of hydrogen and helium (in gas giant planets). There's very little "stuff" to build things with.

How much energy can be meaningfully stored in this small amount of matter? A puny amount of energy can be converted into chemical bond energy. A much larger amount of energy can be stored in gravitational potential energy (lifting matter to near stellar escape velocity).

But beyond that? The only place to store larger amounts of energy is in interstellar mass streams. Accelerating laser sailbots up to relativistic speeds is a way to store large amounts of energy, but this storage medium doesn't stay still. By its very nature, it moves, and it moves so fast that it isn't really a "storage" system within a single star system. In order to store energy for long periods of time, you need the mass stream to cruise along in interstellar space.

However, if you have access to a black hole or neutron star system, it makes more sense to deliver matter to that system. Matter in a black hole system only provides a specific energy of up to .5mc^2, but this energy may be utilized at any time rather than upon a precalculated schedule. Having access to a black hole or neutron star really changes the whole game.

Which gets back to my point that not all star systems are equally desirable. Some are many orders of magnitude more powerful than others.

Githyanki
2011-Dec-07, 01:11 AM
Actually, no probes were sent to this system; see, we have a "G-class" star and the aliens evolved on an, "M-class" so "G-class" stars are considered too hot and have planetary-systems unstable for the chances of alien-life to evolve. The conditions on a world orbiting the HZ of an M-class star are so constant and life needs at least 10 billion years to evolve complex life. The probes never arrived.

eburacum45
2011-Dec-07, 01:51 PM
I'm not convinced that a homeworld capable of delivering billions of colonists per year will not be neighbor to colonies which are themselves population in trillions or beyond. That seems entirely reasonable. The only scenario I can imagine where a colony could achieve a high ITB quickly would be if they deliberately chose to do so at the expense of expanding within their own system.

A significant portion of a star's energy could be collected relatively cheaply, by constructing a series of lightweight statites from a small number of asteroids. These could beam power to rocky moons and planets in order to quickly convert their resources into starships (rather than habitats). This could allow a vry high ITB quite quickly, overwhelming other nearby colonies that are still in the first stages of colonisation. Especially if any of those neighbours are wasting time and energy attempting to terraform uninhabitable planets.

Would any species wish to adopt such a strategy? Possibly; they could sweep through a galaxy in a few tens of millions of years. But such an aggressive species could encounter fierce opposition from older, more established species (if any). What I'm describing is basically an aggressively self-replicating civilisation, and there might be interstellar laws against that sort of thing.

iquestor
2011-Dec-07, 04:28 PM
:rolleyes:
This whole quibble originates with your statement:
“Please cite the SETI page where it talks of searches in other galaxies.”
Now, had you read the paper you’d have understood what I said about SETI listening only at “galactic” distances...
Yes, RAF, it seems rather clear.

So what is it you’re disagreeing with exactly, the ranges of distance as given in the paper?




Eh? You want “thanks” for agreeing with me in some other thread, even while your nature is admittedly disagreeable?
:boohoo:



Thanks!

R. A. F said:
...and if it wasn't obvious, I am so out of this thread...

A DIM wasnt the only one who considered your response curt and insulting. It was plainly obvious to myself as well that A DIM was talking about Intra-Galactic distances and responding to local artifact searches within the solar system, both within the context of the paper. I started to comment after you posted that, but I figured Id let A DIM handle his own battles and might not appreciate me saying something, especially if he took it in a different context than I did. Apparently he saw it the way I did, and so I'm putting my two cents in..

Based on your initial response I also quickly drew the conclusion that you hadn't read the paper -- precisely because if you had (I reasoned) you would easily infer the context in which his statements were made. Either that or you did read it, didn't understand it, and were unable to infer the context. A DIM seemed to give you the benefit of the doubt and assumed the latter, by his very polite reponse to you. But of course you had to turn his polite response into an insult.

You wanna talk about predictable? Sheesh! It seems to me (from the posts of yours I have read) as if you want to be insulted and look for every opportunity to be insulted so that you can criticize, demean and generally insult other posters here. You start with some curt response or challenge that is out of context. Then they reply and you further aggavate the issue, derailing the thread. When they respond, you then reply a final time, and then state some version of "I am so outta here..." as if your departure actually carried some penalty for those of us who want to discuss the topic at hand without being annoyed by posts designed to be irritating. The fact you included ".. and if it werent obvious.." just underlines how often you do this, and how annoying it is to those of us who are here to discuss and learn.

</rant>

transreality
2011-Dec-07, 10:02 PM
Would any species wish to adopt such a strategy? Possibly; they could sweep through a galaxy in a few tens of millions of years. But such an aggressive species could encounter fierce opposition from older, more established species (if any). What I'm describing is basically an aggressively self-replicating civilisation, and there might be interstellar laws against that sort of thing.

Perfectly normal for a species to replicate at its maximum rate. The more typical ecological factors will rule; carrying capacity, population growth rate, migration rate.

So, if life everywhere has profound difficulties in surviving long term space travel, which is not unreasonable since evolution works in insulated biospheres, then the ITB will be naturally close to zero. We can imagine that expensive advanced technology could alleviate this but that as the ecological imperative approaches for such activity, the cost will be less affordable. That is, a society that can afford the surplus for interplanetary transportation, is better off putting that surplus into occupying their local ecospace.

SkepticJ
2011-Dec-08, 01:40 AM
Who says that advanced aliens would be biological? Or that they'd lack the intelligence to not overpopulate?

transreality
2011-Dec-08, 03:11 AM
Who says that advanced aliens would be biological?

as long as they consume resources ecology will apply.


Or that they'd lack the intelligence to not overpopulate?

like?

SkepticJ
2011-Dec-08, 05:21 PM
as long as they consume resources ecology will apply.

True, but machines can power down for practically indefinite periods of time. Complex organic life, at least on Earth, can't do this. Some bacteria have survived millions of years dormant in salt deposits, though.

So all they'd have to do is coast between the stars in a state of near zero energy use. Interstellar starlight being enough to sustain them.


like?

There are no extant examples, but that doesn't mean it's not possible.

IsaacKuo
2011-Dec-08, 07:45 PM
There are many species which don't overpopulate. Typical territorial species control their own population density to ensure that there is enough food available to survive. Neither extreme levels of intelligence nor centralized planning are required for this to work.

whimsyfree
2011-Dec-08, 08:08 PM
There are many species which don't overpopulate. Typical territorial species control their own population density to ensure that there is enough food available to survive.

That would correspond to a working private property system in human societies.


Neither extreme levels of intelligence nor centralized planning are required for this to work.

Centralized planning tends to make it not work.

Actually I think over-population is just a bugbear. Every modern society has a low or negative rate of population growth. The ones that are still growing fast are the least developed countries.

Gomar
2011-Dec-08, 08:11 PM
If an alien space ship capable of travelling here, reproducing itself, and then refuelling the copy and travelling on,... does the probe ask permission to start exploiting the resources of an alien solar system?

correct. There is only 1 planet in the solar system that is solid that has wood, coal, oil, gas, water, energy, food,
animals, plants, etc. ...Earth. Now, has there ever been alien mining for anything anywhere? Any machines or tools
left behind? No. Thus, no such machines exist.
BTW, this reminds me of 2010 replicating monoliths. Eventually, they cover Jupiter. Anything noticeable? Any radio
beacons or signals?

Paul Wally
2011-Dec-08, 09:19 PM
True, but machines can power down for practically indefinite periods of time. Complex organic life, at least on Earth, can't do this. Some bacteria have survived millions of years dormant in salt deposits, though.

So all they'd have to do is coast between the stars in a state of near zero energy use. Interstellar starlight being enough to sustain them.



There are no extant examples, but that doesn't mean it's not possible.

I find the organic life - machine dichotomy to be rather fuzzy. Living organisms are machines too (in many respects), the only difference is that they are naturally evolving whereas machines are designed. Now if we consider the possibility that machines can evolve naturally (genetic algorithms etc.) and that life can be designed (genetic engineering), we may just as well drop the whole distinction. What about the possibility of wetware-hardware intergration, DNA-computation, biomechanical technology, bionics... the boundary between the articial and the natural is becoming more and more fuzzy.

SkepticJ
2011-Dec-08, 10:28 PM
correct. There is only 1 planet in the solar system that is solid that has wood, coal, oil, gas, water, energy, food,
animals, plants, etc. ...Earth. Now, has there ever been alien mining for anything anywhere? Any machines or tools
left behind? No. Thus, no such machines exist.

Your conclusion is rock-solid. We've explored our entire solar system in extreme detail: every asteroid, comet, moon, planet, Kuiper belt and Oort cloud body has been mapped down to the cubic meter. Also, we have have time machines, because we know that no asteroids, comets, moons, Kuiper belt or Oort cloud objects have ever been completely disassembled across the billions of years our solar system has existed. Also, since none have visited our solar system, it follows that none have ever visited any other solar systems.

Our wood, coal, gas, food, animals, plants . . . you're serious? You think an interstellar civilization has any need of such? This isn't Golden Age sci-fi.

Interstellar probes/civilizations would need energy and matter to build things with. That's it. They don't need to mine planets with their strong, inconvenient gravity wells unless they want to build something like a Dyson sphere. They'd need to mine comets for organics and water, asteroids for metals, and that's basically it.

You're projecting that their needs would be anything like ours. When they're far more likely to be immortal machines that spend their time around black holes, pulsars, or red dwarfs. Or doing something else that we haven't yet conceived of--we're like earthworms thinking about what a human would do.

SkepticJ
2011-Dec-08, 10:58 PM
I find the organic life - machine dichotomy to be rather fuzzy. Living organisms are machines too (in many respects), the only difference is that they are naturally evolving whereas machines are designed. Now if we consider the possibility that machines can evolve naturally (genetic algorithms etc.) and that life can be designed (genetic engineering), we may just as well drop the whole distinction. What about the possibility of wetware-hardware intergration, DNA-computation, biomechanical technology, bionics... the boundary between the articial and the natural is becoming more and more fuzzy.

The difference is machines are built of tougher stuff. Compare high strength alloys, carbon fiber, nanotubes, or diamond to bone. Aramid, ultra-high-molecular-weight polyethylene or nanotubes to spider silk. Fused quartz optics to the lenses of our eyes. Corundum, tungsten carbide, or diamond to tooth enamel.

There are very few biological materials left that are better than what modern science and engineering have given us. In time, those too will be bettered.

Why keep any flesh when it doesn't work as well?

DataPlumber
2011-Dec-09, 01:21 AM
"...and if it wasn't obvious, I am so out of this thread..."


Thanks!

It seems that some guys tend to serve the useful purpose of poking holes in fallacious theories, but they also tend to be rather pedantic and tend to twist other's statements into something other than what was originally intended, only to claim some imagined intellectual high ground (such as implying that "galactic" really means "intergalactic"). Although they are quite abrasive in their initial comments, they become hyper-sensitive when their "opponent" counters with a much more diplomatic response.
It can be quite a challenge to deal gracefully with the logical equivalent of John Cleese's Argument Department, but one has to keep one's Zen-frame-o-mind centered from the start, since they ultimately strive to push their "opponent" into a defensive position while others in the thread are actually contributing something to the topic.
For the most part, kudos on your Zen.

Paul Wally
2011-Dec-09, 10:00 AM
The difference is machines are built of tougher stuff. Compare high strength alloys, carbon fiber, nanotubes, or diamond to bone. Aramid, ultra-high-molecular-weight polyethylene or nanotubes to spider silk. Fused quartz optics to the lenses of our eyes. Corundum, tungsten carbide, or diamond to tooth enamel.

There are very few biological materials left that are better than what modern science and engineering have given us. In time, those too will be bettered.

Why keep any flesh when it doesn't work as well?

Strength of materials is not the only factor, and in many instances not the most important factor. You have to look holistically at various considerations like the abundance of raw materials, energy required to process those materials, functionality, versatility etc. Anyway, who's to say that life made of much stronger materials cannot evolve naturally where different minerals are in abundance. It's all relative to what is more readily available where an what is more efficient under what conditions and for what purpose. That's why I don't think there's a real distinction, life is life, whether it is natural or artificial.

IsaacKuo
2011-Dec-09, 03:47 PM
Strength of materials is not the only factor, and in many instances not the most important factor. You have to look holistically at various considerations like the abundance of raw materials, energy required to process those materials, functionality, versatility etc. Anyway, who's to say that life made of much stronger materials cannot evolve naturally where different minerals are in abundance.
The minerals required for much stronger materials are in abundance. Carbon fiber is made of carbon, which is one of the most common substances on Earth and also among biological creatures. Steel is made mostly of iron and carbon, which are both extremely common on Earth. But the efficient processes to create these things were never developed by natural life.

It's not just about materials, but also structures. There are various reasons why animals never developed ball bearings, wheels, or jet turbines. These are reasons why biological life on Earth will never naturally evolve the ability to expand beyond Earth. The barriers to success are simply too wide for random mutations and genetic recombination to solve the problem. Only purposeful design by technological intelligences can solve the problems.

It's all relative to what is more readily available where an what is more efficient under what conditions and for what purpose. That's why I don't think there's a real distinction, life is life, whether it is natural or artificial.
There's at least one big distinction. The way biological evolution works, every feature that evolves must have some survival value for the genetic lineage. But machines are designed and built purely for the benefit of other beings which are completely unrelated. Something like the Hubble space telescope would never evolve naturally. It can't even reproduce, much less preserve any lineage. And even for the actual users, it's a one-off device. It makes more sense to develop different telescopes than to simply duplicate Hubble.

Extrasolar
2011-Dec-09, 05:15 PM
Interstellar probes/civilizations would need energy and matter to build things with. That's it. They don't need to mine planets with their strong, inconvenient gravity wells unless they want to build something like a Dyson sphere. They'd need to mine comets for organics and water, asteroids for metals, and that's basically it.

You're projecting that their needs would be anything like ours. When they're far more likely to be immortal machines that spend their time around black holes, pulsars, or red dwarfs. Or doing something else that we haven't yet conceived of--we're like earthworms thinking about what a human would do.

Aren't you both assuming a lot?

SkepticJ
2011-Dec-09, 09:52 PM
Aren't you both assuming a lot?

I'm assuming they'd have fusion reactors and molecular manufacturing. I think interstellar travel is extremely unlikely without both. Also, I'm assuming they're not stupid.

transreality
2011-Dec-09, 10:23 PM
How big are these probes? nanoscale, or the size of the ship in rendevous with rama?

how much organics they require to construct would make huge impact on where the probe would source its construction materials. For many reasons earth would be the goldilocks planet to plunder. Organics, metals, rare earth elements, water in available in concentrations.

But by the time you assign such characteristics as immortality, perfect reproduction, 100% efficiency, invisibility, unspecified interstellar drives, unfathomable intellects, how are these different to any other UFO?

SkepticJ
2011-Dec-10, 12:32 AM
How big are these probes? nanoscale, or the size of the ship in rendevous with rama?


Nanoscale, I doubt. Cosmic radiation would shred anything of that scale without shielding. Plus they'd have no way to slow down in the target system. Not enough surface are for light pressure to work on, and certainly not the reaction mass.

I imagine they could be fairly small, though. Smaller than the Space Shuttle. And only that large because fusion reactors can't be scaled down too small before they use more energy to contain the plasma than they produce.


how much organics they require to construct would make huge impact on where the probe would source its construction materials. For many reasons earth would be the goldilocks planet to plunder. Organics, metals, rare earth elements, water in available in concentrations.

Comets have plenty of organics. They're not just "dirty snowballs", they're filthy. Comet nuclei reflect very little light, tar has an albedo over twice that of a typical nucleus.

You do know how the Earth formed, right?


But by the time you assign such characteristics as immortality, perfect reproduction, 100% efficiency, invisibility, unspecified interstellar drives, unfathomable intellects, how are these different to any other UFO?

Are you familiar with strawmen?

Machines are immortal. They're not yet able to reproduce themselves from raw materials, but there's no reason why advanced machines couldn't.

I don't believe I, or any serious nanotechnology proponent claims that the technology would be error-free.

100% efficiency is physically impossible.

Invisibility is physically possible, within limits. Familiar with radar stealth technology? Metamaterials? Or as-yet unrealized optical phased arrays?

Interstellar drive:

Fusion torch ramscoop

Solar sail

Medusa

Remember Newton's first law: once it's going, it goes, goes, goes. A journey of centuries to many thousands of years means nothing to something that is ageless and can stay mostly powered down for those spans of time.

Gomar
2011-Dec-10, 03:42 PM
or the size of the ship in rendevous with rama?

For many reasons earth would be the goldilocks planet to plunder. Organics, metals, rare earth elements, water
in available in concentrations.

FYI, Morgan Freeman is playing the prez in the Rama movie. No surprise.
Earth is the only logical reason to visit this solar system. Otherwise, it's a wasteland of same old planets, rocks, dirt, etc.
Fine, alien probes might not need coal or gas or wood, but nuclear energy instead. Now that we have it, I am expecting
a visit from planet Zorkon any day now.

SkepticJ
2011-Dec-10, 08:10 PM
Earth is the only logical reason to visit this solar system.

How arrogant.


Fine, alien probes might not need coal or gas or wood, but nuclear energy instead.

If you've got nuclear fusion reactors, you don't need fissionable heavy elements.

whimsyfree
2011-Dec-11, 04:57 AM
The minerals required for much stronger materials are in abundance. Carbon fiber is made of carbon, which is one of the most common substances on Earth and also among biological creatures. Steel is made mostly of iron and carbon, which are both extremely common on Earth. But the efficient processes to create these things were never developed by natural life.


What, is h.sapiens not "natural life"?



There's at least one big distinction. The way biological evolution works, every feature that evolves must have some survival value for the genetic lineage. But machines are designed and built purely for the benefit of other beings which are completely unrelated.

Manufactured machines are not yet life; but there is no reason why machines could not reproduce without perfect fidelity. If they did then they would be subject to the same evolutionary laws as natural life.

SkepticJ
2011-Dec-11, 07:42 PM
What, is h.sapiens not "natural life"?

We are natural life, our technology (for the most part) is not part of our bodies.


Manufactured machines are not yet life; but there is no reason why machines could not reproduce without perfect fidelity. If they did then they would be subject to the same evolutionary laws as natural life.

True. But machines could conceivably be different, too: capable of self-evolution. If they could use a new feature, they design it in their minds and grow it.

If you had the choice of doing it this way, why would you bother with random mutations and natural selection? Machines capable of self-evolution would far outcompete machines incapable of it. Compare humans to other animals. We don't have claws, we make knives. We make spears, bows, guns . . .

whimsyfree
2011-Dec-11, 09:43 PM
True. But machines could conceivably be different, too: capable of self-evolution. If they could use a new feature, they design it in their minds and grow it.

If you had the choice of doing it this way, why would you bother with random mutations and natural selection?

Whether the mutations are random or directed natural selection applies. Ideas that lead to more idea generators will out number ideas that don't. In particular, those with the will to reproduce and dominate rivals will overwhelm those without.

SkepticJ
2011-Dec-11, 11:41 PM
Whether the mutations are random or directed natural selection applies. Ideas that lead to more idea generators will out number ideas that don't. In particular, those with the will to reproduce and dominate rivals will overwhelm those without.

Directed traits would happen orders of magnitude faster. So natural selection would favor those who could direct their own evolution.

In biological organisms and machines that can't direct their course of evolution, populations evolve. Not individuals.

"Species" isn't a useful concept for machines like I'm talking about. A daughter-machine could change itself to be completely alien to its parent. And its new traits could be heritable, semi-heritable, or non-heritable. Memory could be passed across generations, between peers. Not just stories, but the actual perceptions. Born with thousands of years worth of experience.

DataPlumber
2011-Dec-12, 01:24 AM
I'm sure it must have been theorized before, that maybe we are the SRPs?

SkepticJ
2011-Dec-12, 01:44 AM
That's pretty unlikely for the previously elucidated reasons, viz. we're crappy machines.

We have a fossil record here going back to 3.5 BYO bacteria, and every indication is that we're one of the products of all that evolution.
Mighty inefficient way to get probes.

Plus we don't seem to be doing any probe-like activities.

DataPlumber
2011-Dec-12, 02:15 AM
Yea, with a supposed 13+ billion year old universe, 3+ billions years is a long wait for any response. And, I wonder what specifically we would be responding to/with aside from "nice beaches.. wish you were here"?

Paul Wally
2011-Dec-12, 10:36 AM
True. But machines could conceivably be different, too: capable of self-evolution. If they could use a new feature, they design it in their minds and grow it.

.

I'm not sure what you mean by "self-evolution", but if you mean that the machine runs some kind of simulation, then you either need a heuristic rule or you need a machine more intelligent than the machines you're trying to direct. There seems no getting passed the principle of evolution, which is basically trial and error. Only an omniscient machine can self-direct evolution and in that case there is no need for further evolution. It's kind of like Godel's theorem.

In any case, I think you're too focussed on material differences between what you consider to be machines on the one hand and organic life on the other. For advanced intellligent beings the most important part of their being is their consciousness, and they might have the ability to "download" their minds onto any suitable "hardware", whether it be organic or mechanical.

One possible form of inter-stellar travel is to send self-replicating units to the target star system where they replicate to form a giant super-brain or computer. Once this is all set up, the intelligent beings can then travel at the speed of light, by transmitting the information constituting their minds to the super brain where it is uploaded.

eburacum45
2011-Dec-12, 07:08 PM
I'm not sure what you mean by "self-evolution", but if you mean that the machine runs some kind of simulation, then you either need a heuristic rule or you need a machine more intelligent than the machines you're trying to direct. There seems no getting passed the principle of evolution, which is basically trial and error. Only an omniscient machine can self-direct evolution and in that case there is no need for further evolution. It's kind of like Godel's theorem. I am curious as to why you think that. Evolution is an entirely non-sentient process; there is no reason for any entity attempting 'self-evolution' to be omniscient, merely prepared to accept the occasional failure.

One possible form of inter-stellar travel is to send self-replicating units to the target star system where they replicate to form a giant super-brain or computer. Once this is all set up, the intelligent beings can then travel at the speed of light, by transmitting the information constituting their minds to the super brain where it is uploaded. A process that I have advocated in the past, although I'd like to see some analysis of the 'bandwidth' that such a process might be capable of. In order to send a message that contains a faithful copy of a sophont's mind, the message would have to be transmitted very clearly at interstellar distances. It wouldn't be very pleasant to arrive with half one's vital data missing.

Paul Wally
2011-Dec-12, 08:02 PM
I am curious as to why you think that. Evolution is an entirely non-sentient process; there is no reason for any entity attempting 'self-evolution' to be omniscient, merely prepared to accept the occasional failure.


I view evolution as a trial and error process (like an experiment), and therefor it cannot be predicted with certainty. That's the whole point of an experiment.
Now what I mean by omniscient is that the entity must know the outcome of evolution in order to direct it, but since he cannot know the outcome, he cannot direct it. He can only do something random to himself and wait and see. That is not to direct something. In order to direct your own evolution you have to see beyond where you can see now.

SkepticJ
2011-Dec-12, 08:59 PM
I'm not sure what you mean by "self-evolution", but if you mean that the machine runs some kind of simulation, then you either need a heuristic rule or you need a machine more intelligent than the machines you're trying to direct. There seems no getting passed the principle of evolution, which is basically trial and error. Only an omniscient machine can self-direct evolution and in that case there is no need for further evolution. It's kind of like Godel's theorem.

I mean a mechanical organism that can modify itself as it pleases. Evolution is change over time. That's all the word means. Anything that can change its heritable traits by conscious action has directed evolution.

Now that doesn't mean every change they make to themselves is beneficial. They're still subject to selection pressure. But an intelligent being is far more likely to give themselves positive traits than negative. "Hey, I could sure use . . . ," wouldn't include the mechanical equivalents of cancer or deformities. And unless the new traits turn out to be quickly fatal, they can always undo their modifications when they see they were a mistake.


In any case, I think you're too focussed on material differences between what you consider to be machines on the one hand and organic life on the other. For advanced intellligent beings the most important part of their being is their consciousness, and they might have the ability to "download" their minds onto any suitable "hardware", whether it be organic or mechanical.

Tougher materials allow brighter minds. Guess which allows faster thoughts: brains made of diamond processors, or brains made of wet, squishy nerve cells?

whimsyfree
2011-Dec-12, 09:44 PM
The main problem for intelligent machines is how to spend their time. Humans and other animals have intrinsic motivations rooted in their biological evolution. To eat, survive, reproduce, claim territory, build nests, compete with their own kind etc. Unless its creator deliberately programs in such motivations a calculating machine, however super-intelligent, is just a passive lump of metal. People talk about races of super-intelligent machines spreading throughout the cosmos without explaining the machines' motivation. Why would an emotionless machine be any more interested in conquering the galaxy than, say, calculating pi to a google digits? Machines can create new machines or change themselves, but what would be their motivation?

If machines reproduce with perfect fidelity they will keep doing whatever their original non-machine creator told them to do. If not then eventually they will be subject to natural selection and evolutionary change.

Paul Wally
2011-Dec-12, 11:35 PM
I mean a mechanical organism that can modify itself as it pleases. Evolution is change over time. That's all the word means. Anything that can change its heritable traits by conscious action has directed evolution.

Now that doesn't mean every change they make to themselves is beneficial. They're still subject to selection pressure. But an intelligent being is far more likely to give themselves positive traits than negative. "Hey, I could sure use . . . ," wouldn't include the mechanical equivalents of cancer or deformities. And unless the new traits turn out to be quickly fatal, they can always undo their modifications when they see they were a mistake.

Then astronauts putting on a spacesuit for doing space walks and for walking on the Moon should count as evolution too, and when they get home they reverse the modification. I don't see how self-evolution (as you define it), and all the characteristics that you mention, are not also possible with sufficiently advanced medical science.




Tougher materials allow brighter minds. Guess which allows faster thoughts: brains made of diamond processors, or brains made of wet, squishy nerve cells?

Do diamonds conduct electricity? I thought they made rather good insulators because of the strong covalent bonds. ;)

SkepticJ
2011-Dec-13, 01:44 AM
The main problem for intelligent machines is how to spend their time. Humans and other animals have intrinsic motivations rooted in their biological evolution. To eat, survive, reproduce, claim territory, build nests, compete with their own kind etc. Unless its creator deliberately programs in such motivations a calculating machine, however super-intelligent, is just a passive lump of metal. People talk about races of super-intelligent machines spreading throughout the cosmos without explaining the machines' motivation. Why would an emotionless machine be any more interested in conquering the galaxy than, say, calculating pi to a google digits? Machines can create new machines or change themselves, but what would be their motivation?

To survive. All else is recreation.

Who says they're emotionless? That they don't have fun? That they don't calculate pi to a google digits* while they're expanding?

In a chaotic universe, it makes rational sense to expand from the original star system. Not necessarily an exponential expansion in numbers, but more of a spreading out in space. That way no existential threat could ever destroy everyone.

*Why one would want to calculate pi to a google digits is a mystery to me; it goes on forever, so it's not a solvable problem, and the knowledge probably has no use.

SkepticJ
2011-Dec-13, 02:01 AM
Then astronauts putting on a spacesuit for doing space walks and for walking on the Moon should count as evolution too, and when they get home they reverse the modification. I don't see how self-evolution (as you define it), and all the characteristics that you mention, are not also possible with sufficiently advanced medical science.

Are spacesuits hereditary traits?

What does the sufficiently advanced medical science entail? Right, replacing the natural with the artificial. Because it works better.

Do you wear animal pelts when you go out in the rain? No, you wear a Gore-Tex jacket. Do you ride a horse to work? No, you bomb down the road in your climate-controlled automobile.


Do diamonds conduct electricity? I thought they made rather good insulators because of the strong covalent bonds. ;)

Pure-carbon diamond doesn't. There is doped diamond that is a semiconductor. I didn't specify how the processors work, though. They could be nanomechanical logic gates, they could be photonic, they could be phononic.

Or maybe they don't use diamond, but carbon nanotubes, which can be excellent conductors of electricity.

whimsyfree
2011-Dec-13, 03:42 AM
To survive.

Why? Does my PC wish to survive?

SkepticJ
2011-Dec-13, 04:11 AM
Why? Does my PC wish to survive?

Your PC isn't sophont. Doesn't know it exists, and that it's possible for it to not exist. Your PC doesn't have fear. Doesn't have anything to live for.

Do you have trouble accepting that an artificial being could have fear, could have desires and motivations not unlike our own? Why couldn't they? If you think we're just biochemical machines, and we have them, why couldn't sufficiently complex non-biochemical machines have them?

If you don't think we're just machines, that we have a metaphysical component that can't be duplicated artificially, then there's really no further we can go with this discussion. Debating materialism vs. dualism is not something I wish to spend my time on.

eburacum45
2011-Dec-14, 07:49 AM
The idea that an artificial mind must be given a 'will-to-live' is an important one. Without any goal of self-preservation, a perfectly logical AI might decide to shut down at the earliest opportunity. Here's something I wrote for OA that describes an AI project that failed for exactly that reason.
http://www.orionsarm.com/eg-article/4b0ff6031a292

The opposite side of this problem is that an AI with self-preservation instincts that are too strong could expand excessively, or decide to eliminate competitors ruthlessly. Asimov realised all this with his Laws of Robotics -the third Law is concerned with self-preservation, after all - but putting such abstract laws into lines of code is likely to be a difficult task.

eburacum45
2011-Dec-14, 08:01 AM
I view evolution as a trial and error process (like an experiment), and therefor it cannot be predicted with certainty. That's the whole point of an experiment.
Now what I mean by omniscient is that the entity must know the outcome of evolution in order to direct it, but since he cannot know the outcome, he cannot direct it. He can only do something random to himself and wait and see. That is not to direct something. In order to direct your own evolution you have to see beyond where you can see now.
The goal of self-evolution isn't to reach a perfect state immediately, but to direct evolution in an intelligent way. The evolution of the car hasn't happened instantly - the Model-T Ford was not the perfect motor car, but cars have evolved over time as technology has improved. There are plenty of extinct species of car, too. This is a better model of directed evolution than an attempt to get it right the first time.

Paul Wally
2011-Dec-14, 09:21 AM
The goal of self-evolution isn't to reach a perfect state immediately, but to direct evolution in an intelligent way. The evolution of the car hasn't happened instantly - the Model-T Ford was not the perfect motor car, but cars have evolved over time as technology has improved. There are plenty of extinct species of car, too. This is a better model of directed evolution than an attempt to get it right the first time.

In this example the path that the evolution will follow also depends on an environment, just like natural evolution. In this case the environment constitutes the market (wants and needs of people) as well as competition from other vehicle manufactures. Incremental design changes/improvements are analogous to genetic mutation. I would say in this case the evolutionary path is only partially self-directed and the rest is still a function of the environment, just like natural evolution. In the case of self-replicating probes, there could be competition for resources between different machine designs, and again the evolutionary path will also depend on some kind of environment of which the individual machine cannot have complete knowledge. There seems no escaping the natural evolutionary paradigm: The smarter the machines get the more complex the environment gets.

Complete self-evolution I would say is when there is no competition with other "species" of machines, but then there is nothing to measure progress against. What if some other species of machines comes along one day from a distant solar system and starts competing for resources? The self-evolved machines may find themselves unprepared for that eventuality.

eburacum45
2011-Dec-14, 12:37 PM
In this example the path that the evolution will follow also depends on an environment, just like natural evolution. In this case the environment constitutes the market (wants and needs of people) as well as competition from other vehicle manufactures. Incremental design changes/improvements are analogous to genetic mutation.

I mostly agreee with you, except to say that research and development present at least a moderate improvement over genetic mutation as a tool for evolutionary change. The results still have to be tested in the environment, whether that environment is the market or the cold hard vacuum of space.

What if some other species of machines comes along one day from a distant solar system and starts competing for resources? The self-evolved machines may find themselves unprepared for that eventuality.That is certainly a possibility. One mitigating factor is that an advanced civilisation consisting of self-evolving machines might construct vast processors capable of simulating numerous possible scenarios. In fact I've often wondered what the purpose of such hypothetical thinking megastructures might be. Well, they would come in very useful for modelling the future; modellng what the potential effects of various redesigns might be, modelling the effects of various extraneous threats (like alien species) and (perhaps the most pressing) modelling the behaviour of other members of their own civilisation.

Canis Lupus
2011-Dec-14, 02:41 PM
Everyone take notice...this is the "thanks" I get for agreeing with A.DIM...I shouldn't have gone against my nature, and simply have disagreed...



...and if it wasn't obvious, I am so out of this thread...

As part of everyone, I'm taking notice. I hope it works out for you, and any others similarly affected.

The metaphysical, transcendental, Emerson, stated in the opening paragraph of his essay Self-reliance, "Trust thyself: every heart vibrates to that iron string". May your string never rust because of misplaced generosity.

Canis Lupus
2011-Dec-14, 02:52 PM
....I call this second theory the "canoe theory" in the paper because it reflects Easter Island's history: they not only destroyed their own society through deforestation but furthermore, they prevented their own escape by destroying their ability to construct the kinds of canoes they had used to reach Easter Island in the first place...

This is theory, and highly questionable theory at that. It does you little credit to present it as some sort of fact. More to the point, even if fact, it seems inherently faulty to project our collective experiences on potential other civilisations which arise from and present their own complexities. You may perceive it as necessary, however, I see it as pointless. I understand, by virtue of the lack of an alternative if this is your interest, you are more or less forced into such an exercise. If you are to proceed down the path of projecting our experiences onto other yet unknown life forms, you could at least base you conjectures on something more concrete.

caveman1917
2011-Dec-14, 07:20 PM
Anyway, who's to say that life made of much stronger materials cannot evolve naturally where different minerals are in abundance. It's all relative to what is more readily available where an what is more efficient under what conditions and for what purpose. That's why I don't think there's a real distinction, life is life, whether it is natural or artificial.

The problem is that evolution needs a fitness gradient to work on. The intermediate steps towards the thing you're trying to evolve should also increase fitness, otherwise organisms will never get where you want them to get.

That being said, i suppose there is the possibility for it to work under strictly controlled conditions, where the experimenter decides on the selection pressure and lets the organisms that take steps towards his goal survive. But this will take a very long time, and even then it's a long shot, so why not just build the machine you need and get it over with.

whimsyfree
2011-Dec-14, 09:32 PM
Your PC isn't sophont.


You shouldn't use sci-fi words in serious discussion.



Do you have trouble accepting that an artificial being could have fear, could have desires and motivations not unlike our own? Why couldn't they? If you think we're just biochemical machines, and we have them, why couldn't sufficiently complex non-biochemical machines have them?


You seem to have ignored my previous post. Animals have motivations because natural selection put them there. What would give an artificial being motivations?

IsaacKuo
2011-Dec-15, 12:02 AM
Machines don't need a self preservation instinct. Does a heat seeking missile need a self preservation instinct? Obviously not. That would defeat the point.

But machines are generally built with some purpose in mind. The beings who created and/or operated the machines give the machines their motivations. A heat seeking missile is given the motivation to find a heat signature and home in on it.

Self replicating probes could have little or no more motivation than that. They just home in on the signature of, say, a silicate atmosphere and the "warhead" does the rest. Instead of an explosive warhead, it has an printing device to print out more probes out of silicon/silicate.

SkepticJ
2011-Dec-15, 12:07 AM
In this example the path that the evolution will follow also depends on an environment, just like natural evolution. In this case the environment constitutes the market (wants and needs of people) as well as competition from other vehicle manufactures. Incremental design changes/improvements are analogous to genetic mutation. I would say in this case the evolutionary path is only partially self-directed and the rest is still a function of the environment, just like natural evolution.

The key omitted difference, of course, being that designed-things are capable of revolutionary, not just evolutionary change.

Transistors are not an evolution of vacuum tubes. Electric motors are not an evolution of steam engines. Pump-jets are not an evolution of paddlewheels. LEDs are not an evolution of incandescent bulbs. Microwave ovens are not an evolution of wood-burning stoves. Guns are not an evolution of bows and arrows. Radio is not an evolution of semaphore . . .


In the case of self-replicating probes, there could be competition for resources between different machine designs, and again the evolutionary path will also depend on some kind of environment of which the individual machine cannot have complete knowledge. There seems no escaping the natural evolutionary paradigm: The smarter the machines get the more complex the environment gets.

One doesn't have to have complete knowledge to make good choices. Omniscience isn't possible, no matter how spacially distributed ones senses are. It's not possible to absorb reality to enough decimal places to be able to predict the future in detail, even if the universe is purely deterministic. Indeed, the act of trying to predict the future will change the outcome. Computers that perform meteorological calculations require energy to run, put out heat, and their predictions influence the actions of humans, all of which influence what happens in the real world. On long enough time spans, even planets in their orbits aren't predictable.


Complete self-evolution I would say is when there is no competition with other "species" of machines, but then there is nothing to measure progress against.

Sure there is. If someone continues to exist over time, using less energy or resources to perform the same functions, that means that, very generally, they're making good decisions.



What if some other species of machines comes along one day from a distant solar system and starts competing for resources? The self-evolved machines may find themselves unprepared for that eventuality.

Unless the universe is extraordinarily crowded by resource-hungry beings (and from looking at what it looks like, it doesn't seem to be), it makes more sense to just go elsewhere and avoid conflict.

SkepticJ
2011-Dec-15, 12:25 AM
You shouldn't use sci-fi words in serious discussion.

It's okay to talk about sci-fi ideas in a serious discussion, but it's not cool to use sci-fi words?

I don't really grok the sense of that.


You seem to have ignored my previous post. Animals have motivations because natural selection put them there. What would give an artificial being motivations?

Us?

Any self-replicating machine that doesn't have motivations wouldn't continue to exist. So if someone went to the bother of creating the first intelligent self-replicating machines, it'd make sense to give them some desires, wouldn't it?

Paul Wally
2011-Dec-15, 03:58 PM
ScepticJ: That's not quoted from me. :)

iquestor
2011-Dec-17, 11:13 PM
I agree intelligent conscious machines would need some internal sense of purpose, be it artificial or self generated.

Gomar
2012-Jan-03, 12:59 AM
If the purpose of any probe is to search for intelligence, why would it not make contact if it does find any?
Where is the logic in wasting energy to try to communicate with beings millions of years ahead of humans? If in fact, there is or are
probes or ships anywhere around Earth, it has collected enough data by now to make a rational decision as to how to contact humans.

It could jam all radio and tv transmissions and broadcast a message revealing what it is and where it's from, etc. Ifcourse, it might decide to land infront of the white house, but then it'll surely be shot down. Anyway, since no message has been received from any alien probes, we could conclude there are none.

iquestor
2012-Jan-03, 11:00 AM
There are many reasons why intelligence or even just life seeking probes would not make contact. Maybe their purpose is
to locate and classify and report back. Maybe their builders are xenophobes and just want to avoid systems where life has
Already developed. Maybe history has shown contact is very bad for the contactee as it has here on Earth when the technology gap is wide and they are sensitive to that. Maybe they feel like its rude for machines to make contact and they'll be here tomorrow.

Tuckerfan
2012-Jan-03, 11:11 PM
If the purpose of any probe is to search for intelligence, why would it not make contact if it does find any?
Where is the logic in wasting energy to try to communicate with beings millions of years ahead of humans? If in fact, there is or are
probes or ships anywhere around Earth, it has collected enough data by now to make a rational decision as to how to contact humans.

It could jam all radio and tv transmissions and broadcast a message revealing what it is and where it's from, etc. Ifcourse, it might decide to land infront of the white house, but then it'll surely be shot down. Anyway, since no message has been received from any alien probes, we could conclude there are none.Well, first of all, it'd have to be demonstrated that there is intelligent life on Earth. . .

SkepticJ
2012-Jan-08, 07:54 PM
If the purpose of any probe is to search for intelligence, why would it not make contact if it does find any?
Where is the logic in wasting energy to try to communicate with beings millions of years ahead of humans? If in fact, there is or are
probes or ships anywhere around Earth, it has collected enough data by now to make a rational decision as to how to contact humans . . . Anyway, since no message has been received from any alien probes, we could conclude there are none.

Maybe the rational decision is to not contact humans just now? If I was in their place, I probably wouldn't.

Watch a little "reality TV", read some YouTube video comments, look at the infinite clown fight of politics, the insanity of supernatural-based belief systems, the vapidity of fashion, or take note of history. Don't have to look back far, just the 20th Century. WWI, WWII, Joseph Stalin, Cold War, Vietnam, Cambodia, Rwanda, Kosovo.

Idiotic, insane, homicidal, genocidal, xenophobic, psychotic apes are we.

Gomar
2012-Jan-17, 04:20 PM
Idiotic, insane, homicidal, genocidal, xenophobic, psychotic apes are we.

ok, but we humans do have nukes that's why it's a good time for an alien visit; as well as radio, tv, internet, space ships, etc.
In the 21st c. we would know the difference between an alien ship landing and a demon or satan or a witch or an evil God. Had aliens contacted humans or landed say in Egypt or Greece 2000 years ago, then certainly they would've been perceived as either gods or
angels or demons... perhaps that is precisely what happened, and is why we have stories of Adam&Eve, Jesus, Zeus, Neptune,
Satan, angels, Ra, etc...
Dont forget when Cortez came to Mexico the Incas, eventhough they were thousands vs. 500, bowed down to him and surrendered.

In the modern technological age, it is simple to send out messages from a probe to at first say the NSA or KGB, just as a warning,
and then to the human race as a whole. Ifcourse, to prove that this is not a hoax by the Chinese or Russians or some college frat prank,
the aliens would reveal the cure for AIDS, the flu, cancer, rid other diseases, etc. They might show us videos of their world or
themselves by using technology so advanced that no one would accuse Steven Spielberg of faking any of it.
Further, if an alien probe were watching humans for hundreds if not thousands of years, they could show videos from past history
of say Washington or Napoleon or Jesus or Alexander the Great or building of the pyramids or 9/11 or how humans evolved or the
dinosaurs, or any numbers of species that no longer exist.
Simply, it would be easy for an alien probe or a ship to prove what it is to us today if it wants to.

SkepticJ
2012-Jan-17, 09:58 PM
ok, but we humans do have nukes that's why it's a good time for an alien visit; as well as radio, tv, internet, space ships, etc.

So?

I don't think you're comprehending just how far beyond us alien intelligences could be.

You're assuming they care whether we live or die. That's an unwarranted assumption, born of science fiction speculation that aliens would be benevolent. Advanced aliens need not be benevolent, or malevolent. To them, we could be like wildlife. Sit back, watch what happens.


In the modern technological age, it is simple to send out messages from a probe to at first say the NSA or KGB, just as a warning,
and then to the human race as a whole. Ifcourse, to prove that this is not a hoax by the Chinese or Russians or some college frat prank,
the aliens would reveal the cure for AIDS, the flu, cancer, rid other diseases, etc. They might show us videos of their world or
themselves by using technology so advanced that no one would accuse Steven Spielberg of faking any of it.
Further, if an alien probe were watching humans for hundreds if not thousands of years, they could show videos from past history
of say Washington or Napoleon or Jesus or Alexander the Great or building of the pyramids or 9/11 or how humans evolved or the
dinosaurs, or any numbers of species that no longer exist.

And what would this knowledge do? Could it trigger social upheaval? War?

"A person is smart. People are dumb, panicky, dangerous animals and you know it."-Agent K, Men in Black


Simply, it would be easy for an alien probe or a ship to prove what it is to us today if it wants to.

Exactly, if they want to. Maybe they don't want to?

Do naturalists stop crocodiles from killing wildebeest? Male dolphins from raping females? Chimps from murdering one another?

To them, we could rate no higher than insects do to most people.

TheBrett
2012-Jan-24, 12:08 AM
Is it even possible to build a self-replicating, interstellar probe? It takes the technological and economic infrastructure of an entire country to build space probes now, ranging from processing the raw materials to actually building the various components.

SkepticJ
2012-Jan-24, 07:36 AM
Is it even possible to build a self-replicating, interstellar probe? It takes the technological and economic infrastructure of an entire country to build space probes now, ranging from processing the raw materials to actually building the various components.

Theoretically, yes. Not with current technology, certainly, but current technology is no more the technical peak than the ancient Egyptians' chariots.
Technological advancement isn't done by a long shot. We'll be improving things for centuries, at least. Probably longer. We'll likely invent things that are currently thought to be impossible, just like current metamaterial lenses do what was theoretically impossible back in '92: imaging below the diffraction limit of light.

If you're truly interested, and don't mind devoting some time to reading books, check out Engines of Creation (aimed at a popular audience) or Nanosystems (very dense on math, IIRC it was originally a doctoral paper). And you can read online at places like the Foresight Institute (foresight.org) and Nanotechnology Now (www.nanotech-now.com) for stuff that's happened in the last twenty years, inching toward that future.

ravens_cry
2012-Jan-30, 03:54 AM
Well, first of all, it'd have to be demonstrated that there is intelligent life on Earth. . .
Any being that can honestly ask that question counts as intelligent life in my opinion, much less on an intercontinental communications network that traverses the globe and even reaches, in a limited way, into space.
But then, I am an apeling, I am biased favourably towards an apelings tricks.

SkepticJ
2012-Jan-31, 12:52 AM
Any being that can honestly ask that question counts as intelligent life in my opinion, much less on an intercontinental communications network that traverses the globe and even reaches, in a limited way, into space.
But then, I am an apeling, I am biased favourably towards an apelings tricks.

Pretty sure Tuckerfan was being flippant.

Intelligence isn't a binary state, of course. It comes in degrees and in domains, just like other things that, "make man unique among the animals."

Think about the people who're intelligent enough to get doctorates in engineering or physics, but believe in stuff that would make Dale Gribble guffaw. Or philosophers that can dissect the densest, matryoshka-nested arguments, but couldn't do calculus if their life literally depended on it.

ravens_cry
2012-Jan-31, 02:51 AM
Oh, I had a fair guess they were being facetious. I was merely being whatever the reverse of facetious is, intentionally treating a joke seriously.

neilzero
2012-Feb-03, 07:18 PM
How dangerous is it for ET to land in a small town in USA, Iran or Croatia? I've been around here for over 70 years, and I'm not sure. The movies, sitcoms and news infer unexceptably dangerous. The mother ship might stay about Neptune orbit and send miniprobes. AM, FM and analog TV are quite simple compaired to digital TV and satelite up links, so ET might concluded that we have coded our transmissions to prevent them from collecting data. If their technology is vastly different they might not be able to decypher.
Most of the treads here at bautforum.com would give the impression of reasonably intelegent and rational, but that seems to be the exception. How often is the internet acessable even in low earth orbit?
Self replicating probes may be impossible. If possible they can possibly be microscopic and thus undetectable except to a costly dedicated effort to detect microscopic probes. Has any such effort been funded? Is even a very costly search for micorscopic probes likely to fail because we have not even imagined the alien technology? Let's supose one microcopic probe flying in the air at a density of two per cubic kilomerter = about one billion alien probes. Neil

neilzero
2012-Feb-03, 07:37 PM
How dangerous is it for ET to land in a small town in USA, Iran or Croatia? I've been around here for over 70 years, and I'm not sure. The movies, sitcoms and news infer unexceptably dangerous. The mother ship might stay about Neptune orbit and send miniprobes. AM, FM and analog TV are quite simple compaired to digital TV and satelite up links, so ET might concluded that we have coded our transmissions to prevent them from collecting data. If their technology is vastly different they might not be able to decypher. They probably have not invented subspace radio, so the can't ask their home world for technical advice except with very long delays.
Most of the treads here at bautforum.com would give the impression of reasonably intelegent and rational, but that seems to be the exception. How often is the internet acessable even in low earth orbit?
Self replicating probes may be impossible. If possible they can possibly be microscopic and thus undetectable except to a costly dedicated effort to detect microscopic probes. Has any such effort been funded? Is even a very costly search for microscopic probes likely to fail because we have not even imagined the alien technology? Let's suppose two alien probes in the air per cubic kilometer = about one billion microscopic alien probes. Neil