6 ms·

I think it's not unreasonable that we are sort of early to the party. Earth has existed for about 1/3 of the lifetime of the universe (and I think it was only a

by aflag 4y ago

I think it's not unreasonable that we are sort of early to the party. Earth has existed for about 1/3 of the lifetime of the universe (and I think it was only around 8 billion years ago that the galaxy started looking like it does today) and we are only here right now and we don't have enough impact in our environment that would be detectable with our technology from very far away even within the milky way. Considering that in order to get technologically advanced you need some heavier elements to exist, your planet really needs to be formed after a few generations of stars. Then there are a bunch of other factors to get everything right in the planet so that it ends up creating inteligent life. I suspect there's probably intelligent life out there and some may be a lot more advanced than us. But I think it's not unreasonable to think that no life in the milky way quite made it to galactic domination yet. If that's even feasible. It's just very hard to find anything short of that right now. And, even if such life exists in other galaxies, it would be very hard to detect that as well. Plus, they are really far away, so their influence didn't quite have the time to reach here.

ido 4y ago
The lifetime of the universe is so long that it's hard to reason about intuitively. Saturn's rings were formed about 100 million years ago, which is cosmologically speaking a blink of an eye. 1 million years ago is 1/14,000th (0.007%) of the lifespan of the universe, so almost trivially miniscule in cosmological sense. If some sentient alien civilisation got 1 million years head-start on us wouldn't they basically already have achieved any technological advancement possible?
- 867-5309 4y ago
  the fact we have only been bleeding EM radiation for the last hundred years or so only gives us a radius of 100ly for detection - another tiny fraction of the galaxy
  - bluGill 4y ago
    At most. Radio waves follow the inverse square law for attenuation, most of the signals we have sent over the past 100 years are not detectable out that far.
- jonathanstrange 4y ago
  Somebody must be the first, though. It is worth noting that assuming that we're the first (or among the first) seems no less reasonable than assuming we're the only intelligent life. At least it seems like that to me, maybe I've missed some argument.
  - bluGill 4y ago
    All cases of this are astounding. No other life - astounding. Live, but none other intelligent - astounding. We are first, but there will be more - astounding. There is lots of intelligent life - astounding. We are the last - astounding.
  - aflag 4y ago
    It's not unreasonable to assume we are alone. We have no evidence that we aren't. For me that's the strongest claim. What I'm saying is that not seeing any evidence doesn't reduce the probability of no other intelligent life existing that much. There is still a lot of unknowns and we are sort of still in the early phases of the universe, all things considered.
- SkyMarshal 4y ago
  Also worth considering is that humanity is not the first major species to evolve on Earth. Dinosaurs came first, about 230 million years ago, went extinct ~60 million years ago, then humanity came about 1-2 million years ago. Imagine some other planet in the universe (or even our galaxy) that went through similar geological processes as Earth and at roughly the same time, but on which the first species to evolve did not go extinct and instead went on to develop intelligence. That species would have a roughly ~200+ million year head start on humanity. Further, consider the planets at the far edge of the observable universe from Earth, whose light emitted billions of years ago is only just now reaching us, and which are much older than the Milky Way. What if any of those planets went through a similar evolutionary process and developed intelligent life, but billions of years ago. Such species would now be using science and technology completely incomprehensible to, and likely undetectable by, humanity. We're scanning for electromagnetic transmissions, while they're communicating via subspace, superstrings, ninth membrane, or whatever other exotic means. Everything we currently know about physics and the nature of reality would be useless in detecting and analyzing such advanced species. If they happened to detect and visit us, we wouldn't know unless they wanted us to. It's possible there are many planets in the universe on which life evolved, and the subsequent emergence of intelligent life follows some distribution of trial and error. Most planets evolved intelligent life after one or more errors (dinosaurs and the like), but some small percent developed intelligent life first, ahead of the curve.
  - bluGill 4y ago
    > Such a species would now be using technology completely incomprehensible to, and likely undetectable by, humanity. They are undetectable by us, but this isn't because of how good their technology is (though it may well also be that good), but simply because the universe is so large and the speed of light so slow. Even if their first "person" to create a powerful enough radio had the idea to beam a signal directly to earth, it still wouldn't have arrived. That signal would have been sent before I sun even started forming, so there is no reason for them to have had the idea, but even if they did anyway.
    - deleted 4y ago
      [deleted]
- snowwrestler 4y ago
  > If some sentient alien civilisation got 1 million years head-start on us wouldn't they basically already have achieved any technological advancement possible? “Any technological advancement possible” (my emphasis) might exclude technological advances that would make us aware of intelligent life in other star systems. Just because we can imagine things does not mean they are actually possible, even with lots of time to try.
danwee 4y ago
If we are speculating, then this one is my favourite: what if there are other universes out there? With sufficient time civilizations of another universe could move freely between universes. If they can do that, then they probably have tech to be "invisibles" as well. If the multiverse theory is true, then we have an infinite number of multiverses in which an infite number of civilizations could have developed tech to travel between universes and to be invisble. They are here already :D Nah, well, who knows.
- bluGill 4y ago
  Even if you have infinite time, is there enough energy to get between universes?
  - graderjs 4y ago
    Spoken like someone who knows the answer :)
    - bluGill 4y ago
      Is there another universe? Do you know what direction to go to get to this other universe or are you heading out hoping to hit one? How far apart is this other universe? How much energy does this infinite time society need? Probably other similar questions apply, i can't think of any now though. If I knew all that I could go back to my physics textbooks and calculate. Without though, who knows.
sampo 4y ago
> I think it's not unreasonable that we are sort of early to the party. Earth has existed for about 1/3 of the lifetime of the universe Universe begins | 9.2 billion years Earth formed | 0.5 billion years First life | 0.5 billion years First photosynthesis | 3.0 billion years Enough oxygen in air for macroscopic life | 0.5 billion years Now The main work was: (1) Supernovas creating heavy elements. At first, the universe is all hydrogen (and helium). It takes some generations of stars forming, and exploding as supernovas to create and spread around heavier elements, so that a planet like Earth can form, with all the minerals we have. Do we need 9 billion years for this, or could there have been planets with heavy elements, how much earlier? Is Earth among the first possible? (2) It took 3 billion years of photosynthesis, by single-cell microbial life, to produce and accumulate enough oxygen. First the oxygen released into air would go and oxidize the minerals on Earth's surface. Only after the whole rocky surface was oxidized, would oxygen start to accumulate into the atmosphere. Somewhere around 10% or 13% atmospheric oxygen, it was enough that also other than flat, single-cell-layer multicellular macroscopic life could start to form, without the inner cells being starved of oxygen. 3 billion years of repetitive, grunt work by the microbes. (Then it took 0.5 billion years of evolution from the Cambrian evolutionary explosion, to humans.) Compared to these two, the other steps took much less time.
JoeyJoJoJr 4y ago
It kind of blows my mind that of all time that will ever exist in the universe, our existence has been plonked right at the (almost) very very beginning. It somehow seems significant to me. I’m not sure if I could articulate it properly, but of all time that will ever exist, why/how is it we came to be right at the “start”, instead of any other time.

by aflag 4y ago

ido 4y ago

The lifetime of the universe is so long that it's hard to reason about intuitively. Saturn's rings were formed about 100 million years ago, which is cosmologically speaking a blink of an eye. 1 million years ago is 1/14,000th (0.007%) of the lifespan of the universe, so almost trivially miniscule in cosmological sense. If some sentient alien civilisation got 1 million years head-start on us wouldn't they basically already have achieved any technological advancement possible?

867-5309 4y ago
the fact we have only been bleeding EM radiation for the last hundred years or so only gives us a radius of 100ly for detection - another tiny fraction of the galaxy
- bluGill 4y ago
  At most. Radio waves follow the inverse square law for attenuation, most of the signals we have sent over the past 100 years are not detectable out that far.
jonathanstrange 4y ago
Somebody must be the first, though. It is worth noting that assuming that we're the first (or among the first) seems no less reasonable than assuming we're the only intelligent life. At least it seems like that to me, maybe I've missed some argument.
- bluGill 4y ago
  All cases of this are astounding. No other life - astounding. Live, but none other intelligent - astounding. We are first, but there will be more - astounding. There is lots of intelligent life - astounding. We are the last - astounding.
- aflag 4y ago
  It's not unreasonable to assume we are alone. We have no evidence that we aren't. For me that's the strongest claim. What I'm saying is that not seeing any evidence doesn't reduce the probability of no other intelligent life existing that much. There is still a lot of unknowns and we are sort of still in the early phases of the universe, all things considered.
SkyMarshal 4y ago
Also worth considering is that humanity is not the first major species to evolve on Earth. Dinosaurs came first, about 230 million years ago, went extinct ~60 million years ago, then humanity came about 1-2 million years ago. Imagine some other planet in the universe (or even our galaxy) that went through similar geological processes as Earth and at roughly the same time, but on which the first species to evolve did not go extinct and instead went on to develop intelligence. That species would have a roughly ~200+ million year head start on humanity. Further, consider the planets at the far edge of the observable universe from Earth, whose light emitted billions of years ago is only just now reaching us, and which are much older than the Milky Way. What if any of those planets went through a similar evolutionary process and developed intelligent life, but billions of years ago. Such species would now be using science and technology completely incomprehensible to, and likely undetectable by, humanity. We're scanning for electromagnetic transmissions, while they're communicating via subspace, superstrings, ninth membrane, or whatever other exotic means. Everything we currently know about physics and the nature of reality would be useless in detecting and analyzing such advanced species. If they happened to detect and visit us, we wouldn't know unless they wanted us to. It's possible there are many planets in the universe on which life evolved, and the subsequent emergence of intelligent life follows some distribution of trial and error. Most planets evolved intelligent life after one or more errors (dinosaurs and the like), but some small percent developed intelligent life first, ahead of the curve.
- bluGill 4y ago
  > Such a species would now be using technology completely incomprehensible to, and likely undetectable by, humanity. They are undetectable by us, but this isn't because of how good their technology is (though it may well also be that good), but simply because the universe is so large and the speed of light so slow. Even if their first "person" to create a powerful enough radio had the idea to beam a signal directly to earth, it still wouldn't have arrived. That signal would have been sent before I sun even started forming, so there is no reason for them to have had the idea, but even if they did anyway.
  - deleted 4y ago
    [deleted]
snowwrestler 4y ago
> If some sentient alien civilisation got 1 million years head-start on us wouldn't they basically already have achieved any technological advancement possible? “Any technological advancement possible” (my emphasis) might exclude technological advances that would make us aware of intelligent life in other star systems. Just because we can imagine things does not mean they are actually possible, even with lots of time to try.

danwee 4y ago

If we are speculating, then this one is my favourite: what if there are other universes out there? With sufficient time civilizations of another universe could move freely between universes. If they can do that, then they probably have tech to be "invisibles" as well. If the multiverse theory is true, then we have an infinite number of multiverses in which an infite number of civilizations could have developed tech to travel between universes and to be invisble. They are here already :D Nah, well, who knows.

bluGill 4y ago
Even if you have infinite time, is there enough energy to get between universes?
- graderjs 4y ago
  Spoken like someone who knows the answer :)
  - bluGill 4y ago
    Is there another universe? Do you know what direction to go to get to this other universe or are you heading out hoping to hit one? How far apart is this other universe? How much energy does this infinite time society need? Probably other similar questions apply, i can't think of any now though. If I knew all that I could go back to my physics textbooks and calculate. Without though, who knows.

sampo 4y ago

> I think it's not unreasonable that we are sort of early to the party. Earth has existed for about 1/3 of the lifetime of the universe Universe begins | 9.2 billion years Earth formed | 0.5 billion years First life | 0.5 billion years First photosynthesis | 3.0 billion years Enough oxygen in air for macroscopic life | 0.5 billion years Now The main work was: (1) Supernovas creating heavy elements. At first, the universe is all hydrogen (and helium). It takes some generations of stars forming, and exploding as supernovas to create and spread around heavier elements, so that a planet like Earth can form, with all the minerals we have. Do we need 9 billion years for this, or could there have been planets with heavy elements, how much earlier? Is Earth among the first possible? (2) It took 3 billion years of photosynthesis, by single-cell microbial life, to produce and accumulate enough oxygen. First the oxygen released into air would go and oxidize the minerals on Earth's surface. Only after the whole rocky surface was oxidized, would oxygen start to accumulate into the atmosphere. Somewhere around 10% or 13% atmospheric oxygen, it was enough that also other than flat, single-cell-layer multicellular macroscopic life could start to form, without the inner cells being starved of oxygen. 3 billion years of repetitive, grunt work by the microbes. (Then it took 0.5 billion years of evolution from the Cambrian evolutionary explosion, to humans.) Compared to these two, the other steps took much less time.

JoeyJoJoJr 4y ago

It kind of blows my mind that of all time that will ever exist in the universe, our existence has been plonked right at the (almost) very very beginning. It somehow seems significant to me. I’m not sure if I could articulate it properly, but of all time that will ever exist, why/how is it we came to be right at the “start”, instead of any other time.