4 ms·

> For that reason, it seems absolutely absurd to me that someone would say with certainty that life exists elsewhere in the universe. I'm not sure you have a c

> For that reason, it seems absolutely absurd to me that someone would say with certainty that life exists elsewhere in the universe. I'm not sure you have a conception of how truly BIG the universe is. In fact, according to current cosmological evidence, it is infinitely big. But even if we confine our discussion to our Hubble Sphere, there is almost certainly life elsewhere in the universe. It's just that that life might be very, very far away.

verbify 10y ago
My thoughts too. If we knew there were only 10,000 stars, it could seem likely that the chances of life existing are 1/50,000, and we happen to be lucky. But there are over 100 billion stars in the observable universe. I think the law of large numbers applies here. The likelihood of life existing being high enough that we are the only ones, but low enough that our existence isn't winning some 1 in a googolplex chance just strikes me as an anthropocentric conceit.
- Buttons840 10y ago
  The size of the universe is a large number, but the chance of life just forming from chaos is 1/(a large number). So the odds of life elsewhere in the universe is, roughly, a large number divided by another large number. The question is which large number is larger? We don't know how difficult it is to create life. The universe is big, but the difficulty of creating life might be much bigger. Thus. It is not certain that there is life elsewhere.
  - MAGZine 10y ago
    Just today we found the closest star to us to have a planet in the habitable zone. The closest star. But, we struggle to observe it in any capacity. Indeed, only today we did. And that's nothing to say of the next closest star, or the next, or the next, ad (nearly) infinitum. If planets in this zone aren't as rare as we think, life in the universe might also not be as rare as we think. To me, the question is more "where," rather than "if."
  - Tepix 10y ago
    The fact that life appeared on earth very shortly after it formed gives us a good indicator that Abiogenesis may not be that rare. Something that's probably a lot more rare is favorable conditions over a long time period. It took a long time for life on planet earth to evolve into more complex forms. I'm pretty sure we're not the only ones out there. But will mankind and our space neighbours exist long enough to facilitate communication? Is every species that is competitive enough to subdue all other life on its planet doomed to disintegrate due to internal conflict?
- deleted 10y ago
  [deleted]
- svdr 10y ago
  There are over 100 billion _galaxies_ in the observable universe.
- greendestiny 10y ago
  Oh sure it's a particularly human conceit that that number be exactly 1. But it certainly might be that the number is low enough that it will be very very hard for us to ever detect or interact with other life.
- seiferteric 10y ago
  100 billion stars in our galaxy, not the observable universe.
- skissane 10y ago
  Here's one possibility: intelligent life is sufficiently rare yet the universe is sufficiently large that the universe contains a very large number (possibly even an infinite number) of intelligent civilisations, but they are all sufficiently distant from each other in space and/or time that the odds of any of them ever interacting with each other (or even knowing of each others' existence) is extremely low. e.g. imagine a universe containing a million intelligent civilisations, but each of those intelligent civilisations is in a separate galaxy at least 100 million light years apart. If that is our universe, we might not encounter any of those other civilisations in the next million years. The odds of human extinction could easily be higher than the odds of having any contact with them.
  - kbutler 10y ago
    Just see how that worked out for No Man's Sky...
- saiya-jin 10y ago
  the number of stars out there is more like 1,000,000,000,000,000,000,000 pieces, or 1 billion trillion in observable universe. which is just a subset of whole universe. pretty good chances for something out there. hopefully not as xenophobix as humans these days (and more advanced at the same time)
blahi 10y ago
If you think psychology is shoddy science wait until you hear some cosmology! The universe is very big so there MUST be life elsewhere. It just can't be otherwise!
- 0xfeba 10y ago
  Not quite. No one's publishing papers to that effect. What casual science fans and some popular scientists do posit is that the universe is so big, our solar system so average (as far as we know), so it's highly likely that life exists or has existed elsewhere. The alternative is the anthropocentric view that the entire universe was created merely for our viewing pleasure on Earth.
  - cmrdporcupine 10y ago
    Or that the universe is so diverse and complex that assuming that this same rather random event occurs in the exact same way multiple times in many places is also quite arrogant.
    - 0xfeba 10y ago
      No one is claiming that a random event (?) occurs the exact same way. They just use statistics, based on some known factors and yes, a lot of guesses. We know how stars form, how galaxies form, how solar systems form. We know the general consistency of the galaxies around us, and some systems in our same galaxy. It's not a big leap to assume that some percentage of them will be hospitable (for a time) for life, at least life as we know it. I'd say the arrogant views are that the whole universe was created for us, or that life must be thoroughly plentiful throughout the universe. The least arrogant view is that it's somewhere in-between, but more importantly, to always adapt to the latest evidence.
      - blahi 10y ago
        Pulling probabilities out of your behind is not statistics. Currently we have an anecdote and you want to extrapolate from that. That's shoddy science.
camelNotation 10y ago
Everyone always says this, but it seems to indicate more of an inability to grasp how much we don't know about other planets on your part than it does my inability to grasp how large the universe might be. It's entirely irrelevant if the universe is infinitely large if the probability of life arising is infinitely small.

verbify 10y ago

My thoughts too. If we knew there were only 10,000 stars, it could seem likely that the chances of life existing are 1/50,000, and we happen to be lucky. But there are over 100 billion stars in the observable universe. I think the law of large numbers applies here. The likelihood of life existing being high enough that we are the only ones, but low enough that our existence isn't winning some 1 in a googolplex chance just strikes me as an anthropocentric conceit.

Buttons840 10y ago
The size of the universe is a large number, but the chance of life just forming from chaos is 1/(a large number). So the odds of life elsewhere in the universe is, roughly, a large number divided by another large number. The question is which large number is larger? We don't know how difficult it is to create life. The universe is big, but the difficulty of creating life might be much bigger. Thus. It is not certain that there is life elsewhere.
- MAGZine 10y ago
  Just today we found the closest star to us to have a planet in the habitable zone. The closest star. But, we struggle to observe it in any capacity. Indeed, only today we did. And that's nothing to say of the next closest star, or the next, or the next, ad (nearly) infinitum. If planets in this zone aren't as rare as we think, life in the universe might also not be as rare as we think. To me, the question is more "where," rather than "if."
- Tepix 10y ago
  The fact that life appeared on earth very shortly after it formed gives us a good indicator that Abiogenesis may not be that rare. Something that's probably a lot more rare is favorable conditions over a long time period. It took a long time for life on planet earth to evolve into more complex forms. I'm pretty sure we're not the only ones out there. But will mankind and our space neighbours exist long enough to facilitate communication? Is every species that is competitive enough to subdue all other life on its planet doomed to disintegrate due to internal conflict?
deleted 10y ago
[deleted]
svdr 10y ago
There are over 100 billion _galaxies_ in the observable universe.
greendestiny 10y ago
Oh sure it's a particularly human conceit that that number be exactly 1. But it certainly might be that the number is low enough that it will be very very hard for us to ever detect or interact with other life.
seiferteric 10y ago
100 billion stars in our galaxy, not the observable universe.
skissane 10y ago
Here's one possibility: intelligent life is sufficiently rare yet the universe is sufficiently large that the universe contains a very large number (possibly even an infinite number) of intelligent civilisations, but they are all sufficiently distant from each other in space and/or time that the odds of any of them ever interacting with each other (or even knowing of each others' existence) is extremely low. e.g. imagine a universe containing a million intelligent civilisations, but each of those intelligent civilisations is in a separate galaxy at least 100 million light years apart. If that is our universe, we might not encounter any of those other civilisations in the next million years. The odds of human extinction could easily be higher than the odds of having any contact with them.
- kbutler 10y ago
  Just see how that worked out for No Man's Sky...
saiya-jin 10y ago
the number of stars out there is more like 1,000,000,000,000,000,000,000 pieces, or 1 billion trillion in observable universe. which is just a subset of whole universe. pretty good chances for something out there. hopefully not as xenophobix as humans these days (and more advanced at the same time)

blahi 10y ago

If you think psychology is shoddy science wait until you hear some cosmology! The universe is very big so there MUST be life elsewhere. It just can't be otherwise!

0xfeba 10y ago
Not quite. No one's publishing papers to that effect. What casual science fans and some popular scientists do posit is that the universe is so big, our solar system so average (as far as we know), so it's highly likely that life exists or has existed elsewhere. The alternative is the anthropocentric view that the entire universe was created merely for our viewing pleasure on Earth.
- cmrdporcupine 10y ago
  Or that the universe is so diverse and complex that assuming that this same rather random event occurs in the exact same way multiple times in many places is also quite arrogant.
  - 0xfeba 10y ago
    No one is claiming that a random event (?) occurs the exact same way. They just use statistics, based on some known factors and yes, a lot of guesses. We know how stars form, how galaxies form, how solar systems form. We know the general consistency of the galaxies around us, and some systems in our same galaxy. It's not a big leap to assume that some percentage of them will be hospitable (for a time) for life, at least life as we know it. I'd say the arrogant views are that the whole universe was created for us, or that life must be thoroughly plentiful throughout the universe. The least arrogant view is that it's somewhere in-between, but more importantly, to always adapt to the latest evidence.
    - blahi 10y ago
      Pulling probabilities out of your behind is not statistics. Currently we have an anecdote and you want to extrapolate from that. That's shoddy science.

camelNotation 10y ago

Everyone always says this, but it seems to indicate more of an inability to grasp how much we don't know about other planets on your part than it does my inability to grasp how large the universe might be. It's entirely irrelevant if the universe is infinitely large if the probability of life arising is infinitely small.