Why We’ll Have Evidence of Aliens–If They Exist–By 2035(nautil.us)
nautil.us
Why We’ll Have Evidence of Aliens–If They Exist–By 2035
http://nautil.us/blog/why-well-have-evidence-of-aliensif-they-existby-2035
103 comments
I fail to see any reason behind proclaiming 2035 as the deadline within the article. The author could have very well said 2030 or 2040 and it would have been the same article.
> Within two decades, SETI experiments will be able to complete a reconnaissance of 1 million star systems, which is hundreds of times more than have been carefully examined so far. SETI practitioners from Frank Drake to Carl Sagan have estimated that the galaxy currently houses somewhere between 10,000 and a few million broadcasting societies. If these estimates are right, then examining 1 million star systems could well lead to a discovery.
I think he's basing the date on the assumption that we'll have searched 1 million star systems by 2037 and there are a few million broadcasting societies.
Personally I think the odds are pretty damn long, even on the optimistic end of Sagan's and Drake's assumptions. Assuming there are 200-400 billion star systems in our galaxy, that gives us a 1 in 200-400k odds of finding one by 2037? I'll take the bet.
Still a great read, I'm much more fascinated by the idea of artifacts. I believe that the longer we go without finding things, the more seriously we should be thinking about leaving things.
I think he's basing the date on the assumption that we'll have searched 1 million star systems by 2037 and there are a few million broadcasting societies.
Personally I think the odds are pretty damn long, even on the optimistic end of Sagan's and Drake's assumptions. Assuming there are 200-400 billion star systems in our galaxy, that gives us a 1 in 200-400k odds of finding one by 2037? I'll take the bet.
Still a great read, I'm much more fascinated by the idea of artifacts. I believe that the longer we go without finding things, the more seriously we should be thinking about leaving things.
On the optimistic end of Sagan's range, there are "a few million" broadcasting societies, call it 2 million. If there are 400 billion stars, that means that there's one broadcasting society per 20,000 stars. If they're evenly distributed, and we sample 1M stars, then our odds of missing with all 1M samples are negligible (about 1/10^22).
(I don't think that there are a few million broadcasting societies in our galaxy. But if there are, we'd expect to find them soon.)
(I don't think that there are a few million broadcasting societies in our galaxy. But if there are, we'd expect to find them soon.)
I have trouble believing there's more than a handful of spacefaring species per galaxy. Even without FTL travel, one species could fill up all of the habitable planets in a galaxy the size of ours in a few million years or less, thanks to the fact that we breed exponentially. And there's been Sun-like stars for a while now in our galaxy, presumably with Earth-like planets orbiting them. So it's a matter of getting there first.
I wonder if there are intelligent species that are incapable of developing spaceflight due to environmental reasons. For example, an intelligent water-breathing species on a planet that is quite a bit more massive than Earth.
A ship filled with water has a lot more mass than a ship filled with air. That extra mass compared to what we face, combined with starting from a high gravity world, would mean they would need significantly better propulsion systems than we need to get to orbit.
Could this mean that chemical based rockets would not be sufficient for them to do manned spaceflight? If so, they may never establish a manned orbital presence, and a manned orbital presence may be necessary as a stepping stone to interstellar travel.
A ship filled with water has a lot more mass than a ship filled with air. That extra mass compared to what we face, combined with starting from a high gravity world, would mean they would need significantly better propulsion systems than we need to get to orbit.
Could this mean that chemical based rockets would not be sufficient for them to do manned spaceflight? If so, they may never establish a manned orbital presence, and a manned orbital presence may be necessary as a stepping stone to interstellar travel.
If there are a "handful," then there are probably 0 (besides us). You have to believe that there's a very narrow range of values to get precisely to a handful.
Like, the range quoted above is from "10,000 to a few million," so a factor of 200ish from high to low range.
If you think that there are 10, per galaxy, why don't you believe instead that there are 0.3 per galaxy (only off by a factor of 30?)? How much confidence can you have in your highly speculative variables that your output can be constrained down to just a single order of magnitude or so?
Like, the range quoted above is from "10,000 to a few million," so a factor of 200ish from high to low range.
If you think that there are 10, per galaxy, why don't you believe instead that there are 0.3 per galaxy (only off by a factor of 30?)? How much confidence can you have in your highly speculative variables that your output can be constrained down to just a single order of magnitude or so?
By handful I mean < 5.
Probably usually just one.
Because no others would get a chance to evolve, with all the habitable planets quickly being occupied by whichever species figures out interstellar travel first.
I think you have a very Golden-Era-of-Sci-Fi space-opera conquering view of spacefaring.
Why do we need to expand? Our population growth is already levelling off.
Why do we need to send _our bodies_ rather than with AI, or with our consciouses uploaded into computers? (a la Charles Stross' Accelerando or Greg Egan's Diaspora)
If we're sending AI probes around, why do we need to take all resources to the extent that we prevent other species from developing?
Most of the fundamental science that we want to do can be done right here in our own solar system. There's just not a need to expand.
Why do we need to expand? Our population growth is already levelling off.
Why do we need to send _our bodies_ rather than with AI, or with our consciouses uploaded into computers? (a la Charles Stross' Accelerando or Greg Egan's Diaspora)
If we're sending AI probes around, why do we need to take all resources to the extent that we prevent other species from developing?
Most of the fundamental science that we want to do can be done right here in our own solar system. There's just not a need to expand.
Once you have sufficiently advanced technology, unless you also have some kind of totalitarianism, it only takes a few groups of people who disagree about the allocation of resources (or, really, anything else) in this star system and want to leave. And then the same thing happens recursively in whatever star systems they go to, and you have exponential growth until it saturates to cubic or whatever.
Yes, of course, they will be AIs or uploads or body printers. Even for an advanced civilization, shipping bags of meat to other star systems would be wasteful. That doesn't mean they won't want to use resources, or that there would be no evidence of them if they were already here.
edit: There's certainly scenarios in which the first species to explore a galaxy doesn't literally prevent other species from evolving. But that doesn't mean they wouldn't be obviously detectable. The likely number of starfaring species in the galaxy given our observations is zero.
Yes, of course, they will be AIs or uploads or body printers. Even for an advanced civilization, shipping bags of meat to other star systems would be wasteful. That doesn't mean they won't want to use resources, or that there would be no evidence of them if they were already here.
edit: There's certainly scenarios in which the first species to explore a galaxy doesn't literally prevent other species from evolving. But that doesn't mean they wouldn't be obviously detectable. The likely number of starfaring species in the galaxy given our observations is zero.
> There's just not a need to expand.
It doesn't take a need, just a desire. Someone wanting to be able to say, "I went there. I saw it. I got the T-Shirt."
It doesn't take a need, just a desire. Someone wanting to be able to say, "I went there. I saw it. I got the T-Shirt."
They don't need to be spacefaring, just broadcasting. Of course if there are 10,000+ aliens advanced enough to broadcast radio and laser, we do have to wonder why this hasn't led to the galaxy being filled up over the past 5 billion years. Drake's answer to this is that space travel is too expensive, cramped and lengthy to be worth it.
A couple of assumptions here. The first is that our solar system has habital planets from their perspective, I wouldn't completely rule out that there chemistry could be very different to ours. The second is that they need habitable planets. The idea of living in under ground tunnels isn't palatable to us because we evolved in wide open savanahs, an underground, underwater or nocturnal species might not feel the same.
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would need to be a few million broadcasting societies, broadcasting in a way we can detect.
and there could be aliens in other galaxies! we wouldn't detect them by 2035
article was pretty nonsense imho
and there could be aliens in other galaxies! we wouldn't detect them by 2035
article was pretty nonsense imho
discounts great filters
Agreed on it not being clickbait, although I wish he went into more detail about how Sagan et al came up with their estimates, since that seems to be key to his whole argument.
The Drake equation along with the Fermi Paradox are well known in conjunction with SETI's goal for the past several decades. Seth, Frank Drake, Carl Sagan and Jill Tarter have all publicly talked about their justification for being confident in SETI's eventual success. Sagan even wrote a science fiction book about it that was made into a movie.
I've never understood claims like this. For all we know, the universe could be infinite. Yes, that would mean the universe contains an infinite amount of energy and that we'd find dopplegangers of ourselves if we travel far enough, but we can't be sure it's not true. We can't even be more or less confident in one hypothesis vs another.
Articles like this would be more persuasive if they had qualifiers like "Within our observable universe."
Articles like this would be more persuasive if they had qualifiers like "Within our observable universe."
A lot of people don't realize just how much bigger the universe might be than "the observable universe".
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The size of the universe is irrelevant to SETI, since they're just trying to detect alien civilizations in our neighborwood, which would mean the Milky Way.
I thought it had been established that the universe, as a (hyper)volume of spacetime is finite?
That doesn't mean infinity isn't lurking somewhere beyond though.
That doesn't mean infinity isn't lurking somewhere beyond though.
Maybe in theory but I don't think that's something that could be empirically verified. An axiomatic theory is rather a working assumption, because anything else is mathematically intractable. How could anyone understand something that's too big to understand?
My impression is that Multiverse Theories are a fad playing on semantics.
My impression is that Multiverse Theories are a fad playing on semantics.
> For all we know, the universe could be infinite
if an infinite number of trees fall and and nobody is there to hear it, do they make a sound?
if an infinite number of trees fall and and nobody is there to hear it, do they make a sound?
Maybe not clickbait, but he sure buried the lede. Thanks for the TL;DR. Wasn't clear what his point was from a quick skim.
Sounds great, but there is slim chance of finding them, and even if we do, they will be too far away. We should instead prepare to meet the artificial intelligences of tomorrow, which are a sure bet. It will be like Lee Sedol trying to understand AlphaGo, not like the linguist professor from the movie Arrival trying to understand Alien language.
> possible discovery would be have to be made (if they exist).
...and if they want to be found.
...and if they want to be found.
Not quite true. If Aliens exist AND they had radio technology in use [distance from us in lightyears] years ago we will find them by 2035.
Aliens 200 light years away will not detect life on earth for 100 years or so yet (depending on if they are listening and how sensitive their radios are). If they immediately send a reply it will be 200 more years before we can get their reply.
Note that 200 light years is insignificant even on the scale of our galaxy, much less the universe.
What this means is even if we detect aliens that doesn't mean they still exist, we could well detect them, learn about them and then watch as die (war, plague, or any other doomsday scenario) before we can get our "we are here" message to them. That is we might find aliens that do not exist anymore! The universe is large enough that this would not surprise me (though it might be my great-great-great grandchild who discover they have been dead for thousands of years).
Or maybe we will not find any, and then in 2036 discover the first radio transmission of some aliens only a few light years away.
Aliens 200 light years away will not detect life on earth for 100 years or so yet (depending on if they are listening and how sensitive their radios are). If they immediately send a reply it will be 200 more years before we can get their reply.
Note that 200 light years is insignificant even on the scale of our galaxy, much less the universe.
What this means is even if we detect aliens that doesn't mean they still exist, we could well detect them, learn about them and then watch as die (war, plague, or any other doomsday scenario) before we can get our "we are here" message to them. That is we might find aliens that do not exist anymore! The universe is large enough that this would not surprise me (though it might be my great-great-great grandchild who discover they have been dead for thousands of years).
Or maybe we will not find any, and then in 2036 discover the first radio transmission of some aliens only a few light years away.
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Well, yeah, no shit. We're obviously just looking at the "observable universe", which means light-as-it-is-arriving-now.
My amature take on intelligent alien life is that humans as a technological society have developed extremely quickly, if other intelligent species exist and have a focus on technics, then I think it's safe to assume they've developed with as much speed. Continuing with that assumption, it seems extremely unlikely to me that other technological civilizations are at the same point in the timeline as we are, or slightly further ahead. I would imagine them to be massively further ahead. As such, they would surely know about us, but haven't made contact. Why not? I think this is a very important question to ask in the search for other advanced cultures.
All our current physics says that the speed of light is a real limit to travel, and to get close to that requires far more energy that a society is likely to have. I can well believe that aliens if they exist may conclude leaving their solar system is not worth the cost. Sure they could do it, but many will die when their spaceship on the way. Even robot spaceships are unlikely to make it very far (on the scale of the galaxy) before suffering a critical failure.
Thus I can well believe that aliens have colonized the other habitable planets in their solar system and failed at all attempts to do anything more. They might have got one robot to a different star, but that is it.
Of course this assumes they are there before us by a significant amount. Maybe humans are first to reach our level - it is an arrogant idea but we cannot completely discard it until proven wrong.
Thus I can well believe that aliens have colonized the other habitable planets in their solar system and failed at all attempts to do anything more. They might have got one robot to a different star, but that is it.
Of course this assumes they are there before us by a significant amount. Maybe humans are first to reach our level - it is an arrogant idea but we cannot completely discard it until proven wrong.
Even robot spaceships are unlikely to make it very far (on the scale of the galaxy) before suffering a critical failure.
That seems like a limited vision of the possibilities of spaceships. Remember that we're now traveling through space ourselves, and barring self-inflicted problems, we're not in great danger of suffering critical failure.
That seems like a limited vision of the possibilities of spaceships. Remember that we're now traveling through space ourselves, and barring self-inflicted problems, we're not in great danger of suffering critical failure.
Given enough time an asteroid impact presents the possibility of non self inflicted critical failure.
Maybe other life forms have other life spans. If they get 100000 years old the speed of light limit may not be a big issue for them - at least when only traveling around their own galaxy.
Once genetic manipulation advances enough we will probably have much longer lifespans. I haven't completely given up hope that I'm part of the first generation to live forever.
I think humanity as a species is only just beginning to advance technologically. I grew up right when the world wide web was taking off, and at some point in my adult life realized that my generation is the first of its kind. The first for which a chatroom containing American, Japanese, French and Nigerian participants engaging in a realtime conversation from all corners of the globe is not only possible, it's normal.
I had to step back for a moment and realize that just 10 years before I was born, such a feat was technically possible, but required massive planning and a high degree of skill involved in all participants.
100 years prior, it was impossible.
The rapid exchange of information afforded by this technological advance is utterly disruptive, and our society is still figuring out what to do with ourselves now that we're no longer separated from each other by huge stretches of travel time and long delays in information exchange. I must wonder, then, if this is the turning point in any global civilization? The part where the intelligent beings on a world can actually work together to solve problems at such a larger scale than any individual can observe.
I had to step back for a moment and realize that just 10 years before I was born, such a feat was technically possible, but required massive planning and a high degree of skill involved in all participants.
100 years prior, it was impossible.
The rapid exchange of information afforded by this technological advance is utterly disruptive, and our society is still figuring out what to do with ourselves now that we're no longer separated from each other by huge stretches of travel time and long delays in information exchange. I must wonder, then, if this is the turning point in any global civilization? The part where the intelligent beings on a world can actually work together to solve problems at such a larger scale than any individual can observe.
I argue humanity has never left the stone age, when you think about it we are still digging things out of the ground and banging them together. Once we have consumers using biological machines (beyond yeast and horses but things we have written the genetic code for) or manipulating matter at the atomic level then we will have truly passed into a new age.
we are doing both of these things, e.g. CRISPR and LHC
edit: and by "we" I mean some few genious scientists not including myself except by association
edit: and by "we" I mean some few genious scientists not including myself except by association
We are on the cusp I agree but those techniques haven't been found in end user products yet. I think the future of automation will look a lot less mechanical and a lot more biological.
unless you propose how that's useful to the enduser, I don't see the difference. In most cases the technical capability to achieve that would seem like a far higher achievement on it's own, perhaps.
Massively further ahead or massively further behind.
Additionally, I would assume that any "first contact" with an alien entity won't be a face-to-face, lifeform-to-lifeform meet; We're more likely to meet the robotic creations of an advanced alien civilization well before actual living beings.. unless said alien had an extraordinarily long lifespan compared to us.
Additionally, I would assume that any "first contact" with an alien entity won't be a face-to-face, lifeform-to-lifeform meet; We're more likely to meet the robotic creations of an advanced alien civilization well before actual living beings.. unless said alien had an extraordinarily long lifespan compared to us.
I can think of loads of reasons they haven't made contact, from the altruistic (something like the prime directive) to self-preservation interests.
Even if they're massively more advanced, why invite trouble? We're much more intelligent than fire ants but I for one know I'm not in the habit of sitting on fire ant mounds.
These two can go together. If they contact us and we become belligerent, they may be forced to annihilate us. That would be morally reprehensible to them, so the solution is not to make contact.
Even if they're massively more advanced, why invite trouble? We're much more intelligent than fire ants but I for one know I'm not in the habit of sitting on fire ant mounds.
These two can go together. If they contact us and we become belligerent, they may be forced to annihilate us. That would be morally reprehensible to them, so the solution is not to make contact.
"altruistic (something like the prime directive)"
Related to the solutions to the Fermi paradox, explanations for why the putatively abundant aliens have not contacted us need to cover all the aliens. And the "Prime Directive" is a very, very, very particular definition of "altruistic". I, for one, don't even agree that it's altruistic. Even Star Trek, where it has basically magical dramatic force severed from real concerns, couldn't really argue consistently that it was altruistic: http://memory-alpha.wikia.com/wiki/Pen_Pals_(episode)
Why wouldn't there be a species that looks at us, concludes we're ultimately irrelevant, and just converts our solar system into computronium anyhow? Why wouldn't that be the cosmic evolutionary winner?
(They could even altruistically upload us into an equivalent simulation; while I don't particularly "believe" it, my favorite pet solution to the Fermi paradox is that Earth was uploaded an arbitrary amount of time ago and we've just been simulated ever since out of ethical concerns, a simulation which for simplicity and perhaps even ethical reasons has no other civilizations in it. For all we know they actually digitized Earth in the dinosaur era and in realtime it may in fact still be "millions of years ago" if our simulation runs faster than real time.)
Related to the solutions to the Fermi paradox, explanations for why the putatively abundant aliens have not contacted us need to cover all the aliens. And the "Prime Directive" is a very, very, very particular definition of "altruistic". I, for one, don't even agree that it's altruistic. Even Star Trek, where it has basically magical dramatic force severed from real concerns, couldn't really argue consistently that it was altruistic: http://memory-alpha.wikia.com/wiki/Pen_Pals_(episode)
Why wouldn't there be a species that looks at us, concludes we're ultimately irrelevant, and just converts our solar system into computronium anyhow? Why wouldn't that be the cosmic evolutionary winner?
(They could even altruistically upload us into an equivalent simulation; while I don't particularly "believe" it, my favorite pet solution to the Fermi paradox is that Earth was uploaded an arbitrary amount of time ago and we've just been simulated ever since out of ethical concerns, a simulation which for simplicity and perhaps even ethical reasons has no other civilizations in it. For all we know they actually digitized Earth in the dinosaur era and in realtime it may in fact still be "millions of years ago" if our simulation runs faster than real time.)
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You should read The Three Body Problem series. In the second book, The Dark Forest, it has an extremely plausible answer to the Fermi Paradox: Basically every intelligent civilization is hiding, because Game Theory states if you find aliens, you have to kill them. ( No way of knowing if they are friendly or not, when survival of species is at stake, the smartest move is to kill them immediately just to be safe)
That's the prisoner's dilemma, but the maximum value there is in cooperation, if riskier. To defect still means to rely on the associate to cooperate, which is ratner disenginious and assymetric. Ghere's power in symmetry, but as others pointed out, the existence of a symmetric, ie. comparibly advanced planetary system is unlikely.
having read up on it again I noticed I was a little amis with the values. Still, the total prison time is least for cooperation.
I can only wonder what game theory would have to say about setting the punishments as in the original. Certainly the whole thing is rigged to begin with. Both serve time if none of them admits to the crime? You'd have to be uncooperative with law enforcement out of principle, never mind nature is probably not generally as sinister and draconicly enforcing morally biased laws. The void of deep space rather doesn't care to set traps like that on purpose. But it could randomly. If weights are set arbitrarilly in the thought experiment, what would probabilty theory say then? Nothing, as there are no priors. But what would attacking and extinguishing an unexpecting existence about our own chances to be terminated at once without aprehension?
I can only wonder what game theory would have to say about setting the punishments as in the original. Certainly the whole thing is rigged to begin with. Both serve time if none of them admits to the crime? You'd have to be uncooperative with law enforcement out of principle, never mind nature is probably not generally as sinister and draconicly enforcing morally biased laws. The void of deep space rather doesn't care to set traps like that on purpose. But it could randomly. If weights are set arbitrarilly in the thought experiment, what would probabilty theory say then? Nothing, as there are no priors. But what would attacking and extinguishing an unexpecting existence about our own chances to be terminated at once without aprehension?
I think intelligent alien life is extremely rare. Even with everything right ...:
- Non binary star system
- stable sun
- non gravitational locked planet (thanks moon impact)
- hospitable planet (goldilox zone)
- inner solar system not populated with super giants
- continents and oceans (not a water world)
- magnetic field protecting us from radiation
- planet the right size and the right amount of atmosphere. (i could keep going on)
... we were still owe are existence to an asteroid (among many other things) that wiped out the dinosaurs.
On top of everything, star time scales in the billions of years, evolution hundreds of millions of years, and semi intelligent life within the tens of thousands of years.
if there is other intelligent life out there near by, it either happened billions of years ago or will happen billions of years in the future.
... we were still owe are existence to an asteroid (among many other things) that wiped out the dinosaurs.
On top of everything, star time scales in the billions of years, evolution hundreds of millions of years, and semi intelligent life within the tens of thousands of years.
if there is other intelligent life out there near by, it either happened billions of years ago or will happen billions of years in the future.
If there are 3 billion out of the 300 billion star systems in the galaxy that have habitable planets, then there should be at least 10,000-100,000 star systems that harbor currently brodcasting species, no?
Why would anyone be stupid enough to broadcast location? Ever see independence day? Might be better off not knowing... though .. I think i'd be almost willing to give up life on earth to know... just because I'm curious as hell.
So aliens are going to build city sized ships to travel light years so they can steal the resources of one planet in a star system?
One would guess that aliens with Independence Day technology could figure out how to terraform or build space colonies in their own star system. Even if they ran out of raw material there, surely the next closest one would do.
One would guess that aliens with Independence Day technology could figure out how to terraform or build space colonies in their own star system. Even if they ran out of raw material there, surely the next closest one would do.
Given the population growth rates, and struggle for resources, eventually all alien species will realized its them vs others.
More than mining resources from planets, its generally 'We need to finish them off, before they finish us off'.
More than mining resources from planets, its generally 'We need to finish them off, before they finish us off'.
in the movie, they were after the earths molten core, in the movie thats something rare
We already do it, so... :D
the situation of our planet, all the things i said above (in particular non-gravitational locked, magnetic field, water & continents) is a 1/N event.
I feel like N is very large. When you factor out all the stars of the 100 billion in the milky way, I think you get something unlikely, let alone on a planet in the habitable zone.
also, something on the other side of the milky way (100,000 light years), is also far away, so its not like we have the entire milky way to choose from.
I feel like N is very large. When you factor out all the stars of the 100 billion in the milky way, I think you get something unlikely, let alone on a planet in the habitable zone.
also, something on the other side of the milky way (100,000 light years), is also far away, so its not like we have the entire milky way to choose from.
Using average values in the drake equation, there have been have been 18 million broadcastable civilizations in the milky way.
If we take an average lifespan of 1,000 years and say those cilizations have formed over the last 5 billion years (where planets mostly cooled down throghout the universe) then there are currently only 4-5 broadcastable civilizations in the milky way. Is that correct?
If we take an average lifespan of 1,000 years and say those cilizations have formed over the last 5 billion years (where planets mostly cooled down throghout the universe) then there are currently only 4-5 broadcastable civilizations in the milky way. Is that correct?
IMO intelligence is merely a by product of time, evolution and survival so I don't think it would be that unlikely.
If that were true, why aren't sharks the most intelligent beings on the planet? They've been around in more-or-less their current form since the dinosaurs were around.
Intelligence (as far as we know) requires a brain, which requires a lot of calories to work correctly. Increasing calorie intake requirements is not something that survival-selecting evolution would select for.
Evolution selects for survival, not intelligence. Sharks and other animals have survived very well for millions of years without ever developing a higher level of intelligence. If anything, intelligence seems like it might be a happy mistake of evolution, and potentially very rare since evolution doesn't select for it explicitly.
Intelligence (as far as we know) requires a brain, which requires a lot of calories to work correctly. Increasing calorie intake requirements is not something that survival-selecting evolution would select for.
Evolution selects for survival, not intelligence. Sharks and other animals have survived very well for millions of years without ever developing a higher level of intelligence. If anything, intelligence seems like it might be a happy mistake of evolution, and potentially very rare since evolution doesn't select for it explicitly.
It's probably the right combination of a body, intelligence, social structure and environmental pressures that lead to sophisticated tool making societies that pass their knowledge on down so it accumulates.
So far, we're the only species on Earth to have enough of the right combination to get this far. So maybe it only happens 1 in 1000 worlds with multicellular life.
How many planets does that leave in the Milky Way? That's the sort of calculation SETI does.
So far, we're the only species on Earth to have enough of the right combination to get this far. So maybe it only happens 1 in 1000 worlds with multicellular life.
How many planets does that leave in the Milky Way? That's the sort of calculation SETI does.
you answered your own question in the sentence that followed it. sharks face little pressure to evolve, so they aren’t changing very much
But dinosaurs were around for hundreds of millions of years longer than us.. and there’s no indication they were intelligent or ever built anything
some more, the dinosaurs weren't just stupid (small brained), I believe they were so by design.
I began thinking about it by finding out alligators/crocodiles lived during that time, and they have larger brains. I then wondered why, until I considered the fact that they came from laid eggs, and their 'thing' was the ability to get big when evolution supported it. brains require lots of oxygen and egg shells have limits to how much they can allow through them.
my theory is that they were dumb by design, so that genes could activate and allow them to get really big if it suited them.
I began thinking about it by finding out alligators/crocodiles lived during that time, and they have larger brains. I then wondered why, until I considered the fact that they came from laid eggs, and their 'thing' was the ability to get big when evolution supported it. brains require lots of oxygen and egg shells have limits to how much they can allow through them.
my theory is that they were dumb by design, so that genes could activate and allow them to get really big if it suited them.
Do you have proof they did not build anything? What can resist millions of years?
No, that's what he's saying. There's no indication that they did.
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From reading the article, I don't believe the statement "We’ll Have Evidence of Aliens–If They Exist–By 2035." An alien civilization broadcasting via radio at the same moment we're looking could be very unlikely.
[Edit] Who's to say that we're going to broadcast via radio for thousands or millions of years? What if, in 300 years, we discover a much better system? Then we can reasonably assume that a 400 year radio burst is the sign of a species developing intelligence. We can also reasonably assume that SETI chose a poor indicator in their search.
[Edit] Who's to say that we're going to broadcast via radio for thousands or millions of years? What if, in 300 years, we discover a much better system? Then we can reasonably assume that a 400 year radio burst is the sign of a species developing intelligence. We can also reasonably assume that SETI chose a poor indicator in their search.
Which is why they are also thinking about signals like neutrinos and gravity waves (which are much harder to produce but much better suited to interstellar distances).
While it's never possible to say "everything has been discovered/invented" we know a great deal about the types of particles and waves that can exist at realistic energy levels for use in communication systems because those energy scales have been so well studied. The odds that there is "new physics" to be discovered at a scale that will supplant radio waves for broadcast communications on a terrestrial scale are pretty low.
While it's never possible to say "everything has been discovered/invented" we know a great deal about the types of particles and waves that can exist at realistic energy levels for use in communication systems because those energy scales have been so well studied. The odds that there is "new physics" to be discovered at a scale that will supplant radio waves for broadcast communications on a terrestrial scale are pretty low.
"neutrinos and gravity waves (which are much harder to produce but much better suited to interstellar distances)."
No, they aren't. Both are freakishly difficult to detect, and we have no reason at this point to expect that to ever change. And gravity waves are actually terrible for interstellar distances because it is completely unclear how you would produce a source of gravity waves powerful enough to transmit across interstellar distances, and also transmit in a beam. If you can't transmit in a beam, you're stuck with very unfavorable dropoffs as distance increases.
It is also unclear why, having built the utterly massive complexes for transmission or detection of gravity waves, or the massive complexes required for high-probability neutrino reception (transmission in their case is a bit simpler, though collimating the beam is rough) it would not simply be easier to use electromagnetic waves, which are by comparison so easy that if we had a receiver in another star system we could transmit to them today.
Barring some major revelation in physics, aliens will use electromagnetic waves because everything else is literally (and I mean that in its original correct sense) dozens of orders of magnitude worse. Smart aliens do not demonstrate how much smarter they are than us by using engineering solutions dozens of orders magnitude inferior to what we could build today. However, as my previous text implies and as other commenters have already pointed out, the problem there is that efficiency is obtained at that scale with beams, not broad transmission. The galaxy could be hopping with point-to-point links and they would be much harder for us to notice.
(They wouldn't be impossible, because there would be some scattering on the interstellar medium. But they'd be much more difficult than if we were directly the target.)
No, they aren't. Both are freakishly difficult to detect, and we have no reason at this point to expect that to ever change. And gravity waves are actually terrible for interstellar distances because it is completely unclear how you would produce a source of gravity waves powerful enough to transmit across interstellar distances, and also transmit in a beam. If you can't transmit in a beam, you're stuck with very unfavorable dropoffs as distance increases.
It is also unclear why, having built the utterly massive complexes for transmission or detection of gravity waves, or the massive complexes required for high-probability neutrino reception (transmission in their case is a bit simpler, though collimating the beam is rough) it would not simply be easier to use electromagnetic waves, which are by comparison so easy that if we had a receiver in another star system we could transmit to them today.
Barring some major revelation in physics, aliens will use electromagnetic waves because everything else is literally (and I mean that in its original correct sense) dozens of orders of magnitude worse. Smart aliens do not demonstrate how much smarter they are than us by using engineering solutions dozens of orders magnitude inferior to what we could build today. However, as my previous text implies and as other commenters have already pointed out, the problem there is that efficiency is obtained at that scale with beams, not broad transmission. The galaxy could be hopping with point-to-point links and they would be much harder for us to notice.
(They wouldn't be impossible, because there would be some scattering on the interstellar medium. But they'd be much more difficult than if we were directly the target.)
We're in agreement that gravity waves and neutrinos are harder to produce and detect.
They are better for long interstellar distance communications because their weakly interacting nature and difficult to produce nature means there is no dispersion relationship to worry about, no absorbtion/attenuation issues to worry about, and no noise sources to worry about. The galaxy is a surprisingly difficult medium to send radio waves through if you want them to be received at great distances (difficult medium, not impossible medium). That's one of the things that led early SETI thinkers like Barney Oliver to propose using the spectral Water Hole[0] as a search target.
Gravity waves and neutrinos are harder to produce and detect but the galaxy itself is much less likely to interfere with their propagation if you can produce and detect them. Also, communications uses of gravity waves would presumably be at much higher frequencies so the detector sizes would be much smaller (the size of an interferometer or Weber bar detector is a function of the center detection frequency of the device... sensitivity is largely independent of the size, other than the choice of center detection frequency).
[0] https://en.wikipedia.org/wiki/Water_hole_(radio)
They are better for long interstellar distance communications because their weakly interacting nature and difficult to produce nature means there is no dispersion relationship to worry about, no absorbtion/attenuation issues to worry about, and no noise sources to worry about. The galaxy is a surprisingly difficult medium to send radio waves through if you want them to be received at great distances (difficult medium, not impossible medium). That's one of the things that led early SETI thinkers like Barney Oliver to propose using the spectral Water Hole[0] as a search target.
Gravity waves and neutrinos are harder to produce and detect but the galaxy itself is much less likely to interfere with their propagation if you can produce and detect them. Also, communications uses of gravity waves would presumably be at much higher frequencies so the detector sizes would be much smaller (the size of an interferometer or Weber bar detector is a function of the center detection frequency of the device... sensitivity is largely independent of the size, other than the choice of center detection frequency).
[0] https://en.wikipedia.org/wiki/Water_hole_(radio)
Or more reasonably, assuming only current physics and assuming they mostly stay in their system, they simply don't incur the inefficiency of broadcast radio any more. For example point-to-point using lasers is reasonable, and we'd never see it here unless we were the target.
Radio is likely to be useful for millions of years. Each form of communication has pros and cons. Radio has some advantages over the alternatives, and so we are likely to use it. How much we cannot know without first knowing what the alternative is though.
The alternative is optical which is superior to radio waves at planetary distances and further from the perspective of NASA.
https://www.nasa.gov/directorates/heo/scan/engineering/techn...
https://www.nasa.gov/directorates/heo/scan/engineering/techn...
right, but we are trying to detect on planet communications, which we believe we can do. Once we determine that someone is out there we can ask if/how we can contact them.
But if there are 10,000 to several million of them, then the odds of detecting a signal go up as we look at more stars.
Of course if there's only a few, then we might not see any evidence for them. But 10,000 would probably be detectable at some point in our search.
Of course if there's only a few, then we might not see any evidence for them. But 10,000 would probably be detectable at some point in our search.
These methods focus on finding extraterrestrials with an equivalent or greater technological advancement to our own. How would you find an alien civilization with a 17th-century Earth level of technological development? We were not emitting radio signals or using light pulses to communicate, nor were we flying around in antimatter-powered rockets.
In the main, I think we'd simply have no chance of detecting such civilisations. In the next couple of decades, however, advanced space telescopes with starshade coronagraphs could be able to start doing spectroscopy on exoplanet atmospheres.[1] This would definitely reveal (some kinds of) biologically-active atmospheres, although it wouldn't necessarily to be able to tell the difference between a complex biosphere with a low-tech civilisation, and a uni-cellular algae soup.
I suppose there's an outside chance that such a telescope could detect combustion compounds that are difficult to explain geologically or biologically, and that might be used to hypothesise a civilisation. Something like lead smelting might leave a pretty distinct signature, for example. But that would just lead to a hypothesis, not proof, and I imagine it'd be pretty contentious.
Longer-term, it should be possible to create arbitrarily large space-based optical interferometers[2], to the point where one would be capable of imaging cities and agricultural activity on exoplanets. That'd settle matters (Unless it's under water or impenetrable cloud decks, and then you're just out of luck). But that level of resolution is probably a couple of centuries and/or one singularity away from happening, so don't hold your breath.
1: http://www.planetary.org/blogs/guest-blogs/2017/20170623-sta...
2: https://www.noao.edu/meetings/interferometry/workshop-files/...
I suppose there's an outside chance that such a telescope could detect combustion compounds that are difficult to explain geologically or biologically, and that might be used to hypothesise a civilisation. Something like lead smelting might leave a pretty distinct signature, for example. But that would just lead to a hypothesis, not proof, and I imagine it'd be pretty contentious.
Longer-term, it should be possible to create arbitrarily large space-based optical interferometers[2], to the point where one would be capable of imaging cities and agricultural activity on exoplanets. That'd settle matters (Unless it's under water or impenetrable cloud decks, and then you're just out of luck). But that level of resolution is probably a couple of centuries and/or one singularity away from happening, so don't hold your breath.
1: http://www.planetary.org/blogs/guest-blogs/2017/20170623-sta...
2: https://www.noao.edu/meetings/interferometry/workshop-files/...
We could perhaps detect distant alien life by finding signatures of oxygen or another oxidizer in a planet's atmosphere. These would be highly unlikely to persist long without something alive to keep the thermodynamic gradient up. O2, F2, etc. are extremely reactive.
In the 17th century we were experimenting with static electricity, the sparks of which emit radio waves. You cannot tell them from atmospheric lightening, but they are detectable.
I wonder if an alien species has been listening for a while they might be able to go back in their archives and conclude that some emissions actually were our experiments - once they have hindsight that humans really were playing with static electricity in those time frames.
I wonder if an alien species has been listening for a while they might be able to go back in their archives and conclude that some emissions actually were our experiments - once they have hindsight that humans really were playing with static electricity in those time frames.
>These methods focus on finding extraterrestrials with an equivalent or greater technological advancement to our own.
... AND actually willing to communicate with us, which is not IMHO to be assumed as given.
We need to find a rather "narrow" set of aliens with a technology similar enough to ours, and animated by a similar curiosity about the rest of the universe.
... AND actually willing to communicate with us, which is not IMHO to be assumed as given.
We need to find a rather "narrow" set of aliens with a technology similar enough to ours, and animated by a similar curiosity about the rest of the universe.
Yawn.
All such proclamations, predictions, and earnestness about the Drake Equation is limited, absolutely, by the boundaries of what we currently believe is possible.
To be specific, it has always seemed to me hubris of the first order to presume that we know the principles underlying a more advanced civilization's communications (or, maybe, travel).
We aren't aware of mechanisms more efficient, fast, whatever, than e.g. radiowaves, or, polarized lasers, or [insert latest notion]'.
But what the authors of these things seem to never take seriously is what we don't know, is almost certain to be a lot more significant than what we do.
There is a chart in my office lounge showing the advancement of human symbolic reasoning and technology from pre-history, through 15 years ago.
What is striking to me is that in a few brief thousand years, utterly insignificant evolutionarily speaking, we have gone from first formulating written language and mathematics, to e.g. Cassini, rovers, and LIGO.
Ever if the pace of advancement were plateaued (and it isn't) it is baffling to me that someone would think, oh, we've got the basic constraints now in hand; it's just an exercise of application at this point, to e.g. detect other civilizations.
That doesn't even begin to get into the Liu Cixin style game theory issues...
Anyway. Lack of evidence merely means we're not looking in the right way, IMO.
All such proclamations, predictions, and earnestness about the Drake Equation is limited, absolutely, by the boundaries of what we currently believe is possible.
To be specific, it has always seemed to me hubris of the first order to presume that we know the principles underlying a more advanced civilization's communications (or, maybe, travel).
We aren't aware of mechanisms more efficient, fast, whatever, than e.g. radiowaves, or, polarized lasers, or [insert latest notion]'.
But what the authors of these things seem to never take seriously is what we don't know, is almost certain to be a lot more significant than what we do.
There is a chart in my office lounge showing the advancement of human symbolic reasoning and technology from pre-history, through 15 years ago.
What is striking to me is that in a few brief thousand years, utterly insignificant evolutionarily speaking, we have gone from first formulating written language and mathematics, to e.g. Cassini, rovers, and LIGO.
Ever if the pace of advancement were plateaued (and it isn't) it is baffling to me that someone would think, oh, we've got the basic constraints now in hand; it's just an exercise of application at this point, to e.g. detect other civilizations.
That doesn't even begin to get into the Liu Cixin style game theory issues...
Anyway. Lack of evidence merely means we're not looking in the right way, IMO.
The author of this article is focusing only on SETI-based methods of finding extraterrestrial life. The most promising IMO, and one that I don't see talked about much, is the James Webb Telescope's ability to measure contents of the atmospheres of exoplanets. From what I understand O2 is only known to be created by metabolic processes of living organisms.
Also one thing that's curious to me is the math here assumes these millions of civilizations all exist now or have set up systems to broadcast these beams forever whether or not they go extinct. So if we make the following assumptions:
These civilizations only last a couple hundred years after they create these powerful directional radio wave beams (which if we use ourselves as an example seems to be a reasonable assumption)
One civilizations dies and another sequentially starts broadcasting radio waves (most favorable option)
It takes 2 billion years to create life
Galaxy is about 13 billion years old
There's been about 2M advanced civilizations in the Milky Way
That means there's a 3.6% chance there's a civilizations broadcasting right now. This goes up if some last longer than 200 years, and if some create machines that can broadcast either indefinitely or for a long time. Within 1 magnitude of relative certainty is pretty good I guess.
Also one thing that's curious to me is the math here assumes these millions of civilizations all exist now or have set up systems to broadcast these beams forever whether or not they go extinct. So if we make the following assumptions:
These civilizations only last a couple hundred years after they create these powerful directional radio wave beams (which if we use ourselves as an example seems to be a reasonable assumption)
One civilizations dies and another sequentially starts broadcasting radio waves (most favorable option)
It takes 2 billion years to create life
Galaxy is about 13 billion years old
There's been about 2M advanced civilizations in the Milky Way
That means there's a 3.6% chance there's a civilizations broadcasting right now. This goes up if some last longer than 200 years, and if some create machines that can broadcast either indefinitely or for a long time. Within 1 magnitude of relative certainty is pretty good I guess.
The short version is: "Hypothesis: there are millions of alien civilizations, by 2035 we will have sampled enough possible stars to achieve statistical significance, and either there are no aliens or we'll see a positive result."
Which I agree with (and I also agree with folks who point out that at some point being found may be a bad thing which would encourage hiding).
Like many people I know, I assume there must be other civilizations out there. However it is fun to ask the question, "What if we are unique in all the galaxy?" (really it would be the light cone associated with what we can perceive) What sort of responsibility would it put on humans to get their act together and keep from dying out if we knew we were unique?
Which I agree with (and I also agree with folks who point out that at some point being found may be a bad thing which would encourage hiding).
Like many people I know, I assume there must be other civilizations out there. However it is fun to ask the question, "What if we are unique in all the galaxy?" (really it would be the light cone associated with what we can perceive) What sort of responsibility would it put on humans to get their act together and keep from dying out if we knew we were unique?
Dr. Shostak quoted 2015-2025, in 2008, as the expected dates to discover alien life:
http://www.saukvalley.com/articles/2008/02/12/news/national/...
Just under 10 years later, he quotes 2035.
Not saying he's wrong.
Just under 10 years later, he quotes 2035.
Not saying he's wrong.
What's it called when a research event is always 20 years away?
A key decision for any sentient species would be whether to broadcast one's existence or snoop around quietly first.
This reminds me of a trilogy called Remembrance of Earth's Past by Liu Cixin. He creates a sort of analogy in the second novel, saying civilizations in space should be like hunters in a dark forest (The book is called The Dark Forest). He hypothesizes that you should sneak around quietly, looking to kill others, lest you be killed yourself. I won't say more - it's a great read.
A great summary of the Dark Forest theory without giving away too much of the plot. This trilogy is one of the best books/stories I've ever read.
Secoding the recommendation. The trilogy is incredible.
According to my tinfoil hat, if we plugin sensible defaults to the drake equation, the aliens should have been broadcasting something around 21,000 light years ago for us to get something in 2035.
What if "typical" technological civilizations only go through a very brief period of broadcasting detectable TV signals and then they wire up the entire planet with leak-free fiber optic cables? Then all we can count on is intentional transmissions that say "find us here"?
Presumably, they would still need a way to communicate with remote (unwireable) entities? We find quite a lot of use for devices in orbit. It's hard to imagine that use disappearing, especially as we move towards mining resources in our local solar neighborhood.
We know that humans like to be connected on the go. Wireless works well for this, I'm not sure how to do leak-free fibre to my car (my wife driving - lets be safe here)
So if we don't find evidence of aliens by 2035, we should assume they don't exist? Cynically, I'm pretty sure that's not how this will play out...
Nope, it just means that our estimate for the number of alien civilizations in the galaxy has to decrease, and we needa re-examine the Drake equation.
From the article:
> We can never prove that aliens are not out there, only that they are.
From the article:
> We can never prove that aliens are not out there, only that they are.
> We can never prove that aliens are not out there, only that they are.
No, he's just saying if we don't find them by 2035 he owes the Internet coffee. Pretty excited, though I'm hoping I can substitute tea.
No, he's just saying if we don't find them by 2035 he owes the Internet coffee. Pretty excited, though I'm hoping I can substitute tea.
But the contrapositive is logically equivalent to the original statement. "If aliens exist, we'll have evidence by 2035" is logically equivalent to "If we don't have evidence by 2035, aliens don't exist".
But it won't be taken that way.
Now, I'm overstating the attention-grabbing headline to reflect a greater degree of certainty than Shostak genuinely believes. But he's stating it with more certainty than he genuinely believes, at least in the headline. If he really believed the headline, he'd say, "If we don't find them by 2035, I will believe that they don't exist" instead of "I will buy everyone coffee".
But it won't be taken that way.
Now, I'm overstating the attention-grabbing headline to reflect a greater degree of certainty than Shostak genuinely believes. But he's stating it with more certainty than he genuinely believes, at least in the headline. If he really believed the headline, he'd say, "If we don't find them by 2035, I will believe that they don't exist" instead of "I will buy everyone coffee".
This seems to be the very definition of hubris.
Science can't tell me how to lose weight, but SETI can find intelligent life or the absence of it? Maybe the scientists at SETI are better, or maybe searching for intelligent life is an easier problem?
Didn't Carl Sagan already find the answer by doing math?
Didn't Carl Sagan already find the answer by doing math?
Science knows the mechanics of losing weight. Monitor and restrict calories. For example, lots of people do this successfully with their pets.
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Overall an interesting article by Seth Shostak of the SETI Institute.