4 ms·

We won't, because it doesn't exist within the time period, lifeform type and distance that correlates with ours.

allemagne 11y ago
I'm very suspicious of the hypothesis that our earth is just special or rare. It's a clean solution to the Fermi paradox, but there's no way of knowing this. There's no reason to even think that this is more probable than any other answer.
- deelowe 11y ago
  What if earth isn't special, but the time frame when which life flourishes is extremely small on a cosmological scale? This seems to be the most difficult part for me. Everywhere we look, the universe seems to be a fairly violent place. It may just be that life is common, but short lived. So, due to the distances involved, the chances of life existing in two places at once and being able to observe each other is near 0.
  - lovemenot 11y ago
    From known data, I don't believe your hypothesis is likely to be correct: 1) 13.8 - Age of Universe (Billion years) 2) 4.5 - Age of Earth 3) 3.5 - (minimum) Age of life on Earth Our ancestors have already been alive here for at least 25% of the duration of the universe. To me, the most fascinating number is the small gap between 2) and 3). Suggesting that life here, at least, was almost inevitable. Whether through panspermia or ab initio, it appears difficult neither for life to get started nor to keep hanging around. I read last year about a hypothesis that iirc 100,000 years after the big bang, as the entire Universe was cooling, for some duration it was lukewarm in patches all over. Ideal for the first iteration of life and perhaps for an initial panspermia event that seeded all parts of the expanding universe.
    - deelowe 11y ago
      Interesting. Thanks!
- bobajeff 11y ago
  I remember seeing a documentary on Netflix that pointed out how rare the earth was. They seemed to have a good grasp on the science. They ran the numbers and probability was not in favor of there being many planets like our own. Edit: I think it was called 'The Privileged Planet'.
  - facetube 11y ago
    I looked it up, and it's a documentary arguing in favor of "intelligent design" and against evolution: "Embracing the concept of intelligent design and refuting the theory of evolution, this intriguing video posits that Earth was created not by a series of random events but by a 'creative designer' who knew exactly what he was doing. Several proponents of intelligent design, including philosophers and scientists, share their views about this controversial theory and provide evidence that supports their premise. Actor John Rhys-Davies narrates." I'll pass.
thomasahle 11y ago
There is certainly the possibility that life is just incredibly improbable, and the only reason we think otherwise is oberservers bias.
- lovemenot 11y ago
  True, but can't we at least try to address the likelihood of that being the case. For instance, if we were living on a 9 Billion year old planet but we could only find fossils dating back to 2 Billion years ago, we'd surmise that it took life around 7B to get life started on this planet. Under those circumstances, your hypothesis would be stronger than it is under actual conditions (4.5B and 3.5B respectively).

I'm very suspicious of the hypothesis that our earth is just special or rare. It's a clean solution to the Fermi paradox, but there's no way of knowing this. There's no reason to even think that this is more probable than any other answer.

deelowe 11y ago
What if earth isn't special, but the time frame when which life flourishes is extremely small on a cosmological scale? This seems to be the most difficult part for me. Everywhere we look, the universe seems to be a fairly violent place. It may just be that life is common, but short lived. So, due to the distances involved, the chances of life existing in two places at once and being able to observe each other is near 0.
- lovemenot 11y ago
  From known data, I don't believe your hypothesis is likely to be correct: 1) 13.8 - Age of Universe (Billion years) 2) 4.5 - Age of Earth 3) 3.5 - (minimum) Age of life on Earth Our ancestors have already been alive here for at least 25% of the duration of the universe. To me, the most fascinating number is the small gap between 2) and 3). Suggesting that life here, at least, was almost inevitable. Whether through panspermia or ab initio, it appears difficult neither for life to get started nor to keep hanging around. I read last year about a hypothesis that iirc 100,000 years after the big bang, as the entire Universe was cooling, for some duration it was lukewarm in patches all over. Ideal for the first iteration of life and perhaps for an initial panspermia event that seeded all parts of the expanding universe.
  - deelowe 11y ago
    Interesting. Thanks!
bobajeff 11y ago
I remember seeing a documentary on Netflix that pointed out how rare the earth was. They seemed to have a good grasp on the science. They ran the numbers and probability was not in favor of there being many planets like our own. Edit: I think it was called 'The Privileged Planet'.
- facetube 11y ago
  I looked it up, and it's a documentary arguing in favor of "intelligent design" and against evolution: "Embracing the concept of intelligent design and refuting the theory of evolution, this intriguing video posits that Earth was created not by a series of random events but by a 'creative designer' who knew exactly what he was doing. Several proponents of intelligent design, including philosophers and scientists, share their views about this controversial theory and provide evidence that supports their premise. Actor John Rhys-Davies narrates." I'll pass.

thomasahle 11y ago

There is certainly the possibility that life is just incredibly improbable, and the only reason we think otherwise is oberservers bias.

lovemenot 11y ago
True, but can't we at least try to address the likelihood of that being the case. For instance, if we were living on a 9 Billion year old planet but we could only find fossils dating back to 2 Billion years ago, we'd surmise that it took life around 7B to get life started on this planet. Under those circumstances, your hypothesis would be stronger than it is under actual conditions (4.5B and 3.5B respectively).