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So, when you see that picture of 1 Billion galaxies, each with a few billion solar systems, you think it’s more likely than not we’re alone?

by tcldr 6y ago

onion2k 6y ago
That ignores how likely intelligent life is to arise, which is something we don't know.
lm28469 6y ago
Nobody knows. If only carbon based life is possible and it needs liquid water then, afaik, most of these stars don't have a planet susceptible of hosting life as we know it, and even for the ones with the right conditions we might be a bit early or a bit late. It's hard to quantify the chances of life existing anywhere else at the same time as us when we don't have any idea of how it came to exist in the first place. We might be the exception, we might not. You can't just make the connection: "billion of stars" = "we're not alone". I don't pretend to know what's "likely" on a universal scale and I don't think anyone should
- tcldr 6y ago
  We’re literally looking for evidence that there was carbon life on the planet next door. When you consider that, just in the image provided, there are at least 1B x 1B solar systems. 1e18. Or about as many solar systems as there are grains of sand on the planet earth. Considering that the building blocks of life have been detected on random asteroids arriving on planet earth (https://www.nasa.gov/press-release/goddard/2019/sugars-in-meteorites https://www.nasa.gov/press-release/goddard/2019/sugars-in-me...), and the capacity for intelligence to evolve in distinct branches of our own DNA (https://www.nature.com/articles/nature14668 https://www.nature.com/articles/nature14668), I personally think it’s hard to say that in all likelihood we’re alone.
  - lm28469 6y ago
    > We’re literally looking for evidence that there was carbon life on the planet next door. And we haven't found any. > I personally think it’s hard to say that in all likelihood we’re alone. We simply have no idea. None of our model work at that scale, especially not our intuition or our "statistical" models (we have 1 data point, and it mostly is incomplete). It's like looking at an enormous pile of snow and saying "there must be gold in there, my friend found gold while digging in africa, surely this pile of snow is big enough to contain at least a bit gold". I wouldn't be surprised if life evolved somewhere else, maybe hundreds of time (either in the past, present or in the future), I just don't see how you can claim with absolute certainty that it happened and that we're not alone. Saying with absolute certainty that we're not alone is a guess, just like saying we're certainly alone, we don't have the tools to determine it. If someone shows me an advanced math equation and ask me to solve it I'd say "I don't have the tools" not "it's probably 2"
    - tcldr 6y ago
      > If only carbon based life is possible and it needs liquid water then, afaik, most of these stars don't have a planet susceptible of hosting life as we know it, and even for the ones with the right conditions we might be a bit early or a bit late. My point is, there are likely millions or even billions of planets in that photograph alone, with the perfect conditions for sustaining human life. I can’t say with certainty that there is life, but by God would it surprise me if there weren’t.
hntrader 6y ago
Everything in my gut says we're not currently alone, and if I was offered a wager that was moderated by an omniscient being I'd be happy to bet at 1:10 to 1:50 odds. Of course, nobody has specific evidence either way, this is all guesses through Bayesian reasoning (Anders Sandberg has a paper arguing the opposite to my above guess, along Bayesian lines). But no evidence is distinct from no information.
- tcldr 6y ago
  I think I’m more impressed that the omnipresent being turned out to be a bookmaker :)

So, when you see that picture of 1 Billion galaxies, each with a few billion solar systems, you think it’s more likely than not we’re alone?

by tcldr 6y ago

So, when you see that picture of 1 Billion galaxies, each with a few billion solar systems, you think it’s more likely than not we’re alone?

onion2k 6y ago

That ignores how likely intelligent life is to arise, which is something we don't know.

lm28469 6y ago

Nobody knows. If only carbon based life is possible and it needs liquid water then, afaik, most of these stars don't have a planet susceptible of hosting life as we know it, and even for the ones with the right conditions we might be a bit early or a bit late. It's hard to quantify the chances of life existing anywhere else at the same time as us when we don't have any idea of how it came to exist in the first place. We might be the exception, we might not. You can't just make the connection: "billion of stars" = "we're not alone". I don't pretend to know what's "likely" on a universal scale and I don't think anyone should

tcldr 6y ago
We’re literally looking for evidence that there was carbon life on the planet next door. When you consider that, just in the image provided, there are at least 1B x 1B solar systems. 1e18. Or about as many solar systems as there are grains of sand on the planet earth. Considering that the building blocks of life have been detected on random asteroids arriving on planet earth (https://www.nasa.gov/press-release/goddard/2019/sugars-in-meteorites https://www.nasa.gov/press-release/goddard/2019/sugars-in-me...), and the capacity for intelligence to evolve in distinct branches of our own DNA (https://www.nature.com/articles/nature14668 https://www.nature.com/articles/nature14668), I personally think it’s hard to say that in all likelihood we’re alone.
- lm28469 6y ago
  > We’re literally looking for evidence that there was carbon life on the planet next door. And we haven't found any. > I personally think it’s hard to say that in all likelihood we’re alone. We simply have no idea. None of our model work at that scale, especially not our intuition or our "statistical" models (we have 1 data point, and it mostly is incomplete). It's like looking at an enormous pile of snow and saying "there must be gold in there, my friend found gold while digging in africa, surely this pile of snow is big enough to contain at least a bit gold". I wouldn't be surprised if life evolved somewhere else, maybe hundreds of time (either in the past, present or in the future), I just don't see how you can claim with absolute certainty that it happened and that we're not alone. Saying with absolute certainty that we're not alone is a guess, just like saying we're certainly alone, we don't have the tools to determine it. If someone shows me an advanced math equation and ask me to solve it I'd say "I don't have the tools" not "it's probably 2"
  - tcldr 6y ago
    > If only carbon based life is possible and it needs liquid water then, afaik, most of these stars don't have a planet susceptible of hosting life as we know it, and even for the ones with the right conditions we might be a bit early or a bit late. My point is, there are likely millions or even billions of planets in that photograph alone, with the perfect conditions for sustaining human life. I can’t say with certainty that there is life, but by God would it surprise me if there weren’t.

hntrader 6y ago

Everything in my gut says we're not currently alone, and if I was offered a wager that was moderated by an omniscient being I'd be happy to bet at 1:10 to 1:50 odds. Of course, nobody has specific evidence either way, this is all guesses through Bayesian reasoning (Anders Sandberg has a paper arguing the opposite to my above guess, along Bayesian lines). But no evidence is distinct from no information.

tcldr 6y ago
I think I’m more impressed that the omnipresent being turned out to be a bookmaker :)