Fermi's 'where are they' question? split off another thread....

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This question has a naturally associated question which is how common is life? Not just on earth but anywhere in the universe. To begin making assumptions of the likelihood of life outside of our planet we have to first understand how life arose here first. Since we have not found any evidence of life outside of our planet as of yet, even though our search is only just beginning, we must conclude that at least intelligent life is not that common of a thing. Intelligent meaning capable of building devices using electromagnetic waves that we could detect. If intelligent life were extremely common you think seti would have found something by now. If we have a difficult time finding the distinction of the first forms of life and inanimate molecules here on earth, how would be able to distinguish a life form of an alien race. Maybe they don't use electromagnetic waves but are into some quantum entanglement for communication. It is possible there are other life forms that don't use water, proteins, etc and are of a completely different order than just molecular configurations. It just so happens on this particular planet intelligent life takes the form brains, bones, flesh, etc.. it could be a different story somewhere else. I would like to hear what an astrobioligist would think about an alien made up of some bosonic particles or something alike.
 

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jim mcnamara
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Thread created to handle digression in another thread.
 
  • #3
DaveC426913
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Since we have not found any evidence of life outside of our planet as of yet, even though our search is only just beginning, we must conclude that at least intelligent life is not that common of a thing.
This is a hasty conclusion.

Several solutions to the Fermi Paradox do not require extraterrestrial intelligence to be rare.
Here's a list of possible solutions:
https://en.wikipedia.org/wiki/Fermi_paradoxIt is left as an exercise for the reader to identify which ones don't depend on a paucity of EI.
(But here's a freebie: 7.21)
 
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In the words of "The Hitchhikers Guide to the Galaxy" space is BIG, incredibly BIG, to coin a phrase. Wherever the aliens are, they are so far away we will never know them.
Unless they have developed some really exotic form of instant travel through the galaxy AND they take an interest in our minescule system why would they bother with us. I also suggest that traveling through space at very high speeds would be VERY dangerous to any craft as we know them. What would happen to a craft if it struck a large gas could at relativistic speed. I imagine it would be vaporized. Even with so-called "shields" the energy radiated would be great enough to fry the craft.
We are effectively alone....but I keep an open mind.
 
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DaveC426913
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Wherever the aliens are, they are so far away we will never know them.
Yes but the OP addressed the issue of whether they are common (common enough to be nearby). He drew the same conclusion as you.

Not all solutions to the Fermi Paradox require that, if they exist, they are too far away.
 
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pinball1970
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This question has a naturally associated question which is how common is life? Not just on earth but anywhere in the universe. To begin making assumptions of the likelihood of life outside of our planet we have to first understand how life arose here first. Since we have not found any evidence of life outside of our planet as of yet, even though our search is only just beginning, we must conclude that at least intelligent life is not that common of a thing. Intelligent meaning capable of building devices using electromagnetic waves that we could detect. If intelligent life were extremely common you think seti would have found something by now. If we have a difficult time finding the distinction of the first forms of life and inanimate molecules here on earth, how would be able to distinguish a life form of an alien race. Maybe they don't use electromagnetic waves but are into some quantum entanglement for communication. It is possible there are other life forms that don't use water, proteins, etc and are of a completely different order than just molecular configurations. It just so happens on this particular planet intelligent life takes the form brains, bones, flesh, etc.. it could be a different story somewhere else. I would like to hear what an astrobioligist would think about an alien made up of some bosonic particles or something alike.
This is the estimated range of our radio waves in our galaxy in comparison to the size of the galaxy.
http://www.planetary.org/multimedia/space-images/universe/extent-of-human-radio-broadcasts.htmlIt's possible for lots of those little dots to be occupying the galaxy and not interact with one another for 1000s of years.
 
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This is a hasty conclusion.

Several solutions to the Fermi Paradox do not require extraterrestrial intelligence to be rare.
Here's a list of possible solutions:
https://en.wikipedia.org/wiki/Fermi_paradoxIt is left as an exercise for the reader to identify which ones don't depend on a paucity of EI.
(But here's a freebie: 7.21)
I love the idea of the zoo hypothesis, but you would think there would some evidence somewhere, some signal or code should have made itself known by now. Humans are pretty amenable but can be very clever too given the opportunity. I hate to go down the ancient aliens path because to me there is just not enough evidence to support their claims, but at least they are open minded. The solutions to the fermi paradox are intriguing but we are ignoring a more fundamental question just what is life and is it intrinsic to the universe? Is it just probability or an inevitability?
 
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pinball1970
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I love the idea of the zoo hypothesis, but you would think there would some evidence somewhere, some signal or code should have made itself known by now. Humans are pretty amenable but can be very clever too given the opportunity. I hate to go down the ancient aliens path because to me there is just not enough evidence to support their claims, but at least they are open minded. The solutions to the fermi paradox are intriguing but we are ignoring a more fundamental question just what is life and is it intrinsic to the universe? Is it just probability or an inevitability?
What life is not clear cut and was expanded on the other thread by @DaveC426913
Is the chemistry and conditions on earth that unique in the galaxy?
Probably not given all the possibilities with 200 billion estimated stars in the galaxy.
Intelligent life like us with a suitable technology?
Dinosaurs walked the earth for 150 million years and they did not evolve a suitable intelligence for any sort of communication or technology.
There could be all sorts of life out there that will not make that evolutionary step.
Also remember that life on earth was bacterial for about 2 billion years.
Lastly there have been some large scale extinction events on our planet despite these 'ideal' conditions for life. The Permian Triassic extinction (one of many) event wiped out over 50% of all biological families. That is some Goldilocks zone.
So a few hurdles to get over to make contact.
Abiogenesis, evolve to get smart, build a technology and send out signals whilst avoiding mass extinction.
The species would have to do all this while we are around to pick this up, that is a lot to ask in just 100 years.
If we can stick around for another 100,000 years then our signals would have traversed the entire galaxy and back. I think the question on whether we are alone or not will be clearer then. Until then it's speculation.
 
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What life is not clear cut and was expanded on the other thread by @DaveC426913
Is the chemistry and conditions on earth that unique in the galaxy?
Probably not given all the possibilities with 200 billion estimated stars in the galaxy.
Intelligent life like us with a suitable technology?
Dinosaurs walked the earth for 150 million years and they did not evolve a suitable intelligence for any sort of communication or technology.
There could be all sorts of life out there that will not make that evolutionary step.
Also remember that life on earth was bacterial for about 2 billion years.
Lastly there have been some large scale extinction events on our planet despite these 'ideal' conditions for life. The Permian Triassic extinction (one of many) event wiped out over 50% of all biological families. That is some Goldilocks zone.
So a few hurdles to get over to make contact.
Abiogenesis, evolve to get smart, build a technology and send out signals whilst avoiding mass extinction.
The species would have to do all this while we are around to pick this up, that is a lot to ask in just 100 years.
If we can stick around for another 100,000 years then our signals would have traversed the entire galaxy and back. I think the question on whether we are alone or not will be clearer then. Until then it's speculation.
Yes kudos to Dave who made a great post in the past thread that was diverted here. Apparently conditions on mars were similar to the ones on earth sometime in the past with water and something of an atmosphere. Yet no evidence to life there, no fossilized bacteria, nothing. I feel like earth is just a cosmic stage or prison for lazy particles.
 
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BillTre
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Yet no evidence to life there, no fossilized bacteria, nothing.
Comments like this are of little to no significance.

Even if there were life on Mars, its unlikely that we would have good evidence of its existence at this time.
The Mars rovers could have rolled over Martian bacteria and would not have known it.
There has not been enough detailed study of any other planet to even come close to saying there is no life there. Such statements are getting way ahead of the what is really known.

Methane, which possibly has a biological origin, has been intermittently found there, but other non-biological causes have not been ruled out.
Sorting things like this out will take much more detailed study, probably involving microscopes, biochemistry, and perhaps culturing.
 
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pinball1970
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Yes kudos to Dave who made a great post in the past thread that was diverted here. Apparently conditions on mars were similar to the ones on earth sometime in the past with water and something of an atmosphere. Yet no evidence to life there, no fossilized bacteria, nothing. I feel like earth is just a cosmic stage or prison for lazy particles.
Mars is a good example actually. A good indication besides position to its star is a planets ability to retain water, so looking at the evidence so far
regarding water on Mars.
http://www.astronomy.com/news/2018/07/liquid-water-on-marshttp://www.planetary.org/blogs/emily-lakdawalla/2018/liquid-water-on-mars-really.html
The paper from Science here

https://science.sciencemag.org/content/361/6401/490.full
There were some pretty cool images too showing the sort of erosion rivers and streams have on the landscape.
https://images.app.goo.gl/df3ptsryuZYz7YGk9
It would really important if data coming back from probes and a possible mission there give strong indication of life, ancient life. Two planets in one solar system! That would skew the probabilities just a little bit I think.
I think this where Bayesian statistics may kick in but I am not a mathematician. @phinds @fresh_42 @Mark44 could give an indication on how that could refine the probability possibility.
 
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But, if just one species in the Galaxy had developed the technology and the will for interstellar travel, it could have completely colonized it at sub-light speeds (either with self-replicating robotic probes or in person) within a million years or so.
 
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DaveC426913
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But, if just one species in the Galaxy had developed the technology and the will for interstellar travel, it could have completely colonized it at sub-light speeds (either with self-replicating robotic probes or in person) within a million years or so.
This is a pretty big hypothetical though.

I have a car and a will to travel, but I have not visited even a fraction of the cities in my country. Nor will I ever, even given sufficient time.

I guess if you changed your statement to "the will to colonize as many planets as possible".
 
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But, if just one species in the Galaxy had developed the technology and the will for interstellar travel, it could have completely colonized it at sub-light speeds (either with self-replicating robotic probes or in person) within a million years or so.
Good point. If there are civilizations out there that can travel interstellar space then and hadn't killed themselves off, then they're fingerprints could be ubiquitous around the galaxy. Like the British empire was across the globe once they mastered the seas. What would we do if we discovered a primitive but semi intelligent life form under mars?
 
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pinball1970
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Discuss it on PF
 
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BillTre
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While we can attest to one case of life arising on a planet, of that life attaining higher forms, eventually intelligence and to some extent space technology,
there are zero known cases of a:
species in the Galaxy had developed the technology and the will for interstellar travel

Using the logic often found in these discussions would imply that "species in the galaxy, developing technology and the will for interstellar travel" is a less likely occurence than life arising.
It seems to be a bigger IF.
 
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While we can attest to one case of life arising on a planet, of that life attaining higher forms, eventually intelligence and to some extent space technology,
there are zero known cases of a:


Using the logic often found in these discussions would imply that "species in the galaxy, developing technology and the will for interstellar travel" is a less likely occurence than life arising.
It seems to be a bigger IF.

An interesting 'IF' is if we find evidence of current or past life on Mars, Titan or somewhere else in the solar system, which could happen within the next couple of decades, then it implies life is common across the universe. Combine that with the lack of evidence for interstellar civilizations implies either intelligent technological civilizations are extremely rare or interstellar travel is an intractable problem
 
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pinball1970
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An interesting 'IF' is if we find evidence of current or past life on Mars, Titan or somewhere else in the solar system, which could happen within the next couple of decades, then it implies life is common across the universe. Combine that with the lack of evidence for interstellar civilizations implies either intelligent technological civilizations are extremely rare or interstellar travel is an intractable problem
That makes sense because the chemistry is ubiquitous, that evolutionary step to where we are though seems to be very rare at least on our planet.
Why would it be different elsewhere?
 
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gmax137
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... Like the British empire was across the globe once they mastered the seas...
There's going to be hell to pay when the starships arrive and we find out they use Whitworth fasteners torqued to foot-pounds 😈
 
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There's going to be hell to pay when the starships arrive and we find out they use Whitworth fasteners torqued to foot-pounds 😈


Well maybe, but even so. . . I still think it would be a triumph. . 😈

.
 
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Discuss it on PF
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All joking aside, what we would do could be a good indication what they would do. If we did happen to find some semi intelligent life on Europa or subterranean mars what would be the extent of our interactions. Just purely observational? Probably not, given our scientific curiosity. We would have to take samples, run experiments, and decode their DNA if they have any maybe even exploit them or influence their ideology...sorry a bit too speculative.
 

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