[ExI] 30 Solutions to the Fermi Paradox

[Dan TheBookMan]

On Mar 20, 2021, at 3:09 PM, BillK via extropy-chat <extropy-chat at lists.extropy.org> wrote:
> 
> On Sat, 20 Mar 2021 at 21:05, Dan TheBookMan via extropy-chat
> <extropy-chat at lists.extropy.org> wrote:
>> 
>> I agree that someone has to be first, though it leads to asking why others didn’t get here first. The copernican principle (there’s nothing special about us, here and now, with regard to science) seems a good default position and requires (IMO) some explanation to set aside.
>> 
>> That said, all the good observational evidence seems to lead to your conclusion. But that doesn’t explain why this is so.
> 
> Our galaxy is about 200,000 light years in diameter, so any other tech
> civilisation is likely to be thousands of light years away.  We won't
> be holding a conversation with them.
> 
> This would be obvious to every tech civilisation, so they won't waste
> energy broadcasting. Communication will be direct beamed local
> transmissions. Even just when communicating with Mars rovers, transmission
> time takes between 4 and 20 minutes, depending on the planets orbital
> position. Double that to get a response back.
> 
> Alpha Centauri, our nearest star system, has a 4.3 year transmission
> time. So star systems have to be pretty well self-sufficient.

This isn’t about communication per se, especially not two way communication over the short term, but just mere detection. Why aren’t there artifacts of other technological civilizations?

Also, even given the galaxy’s size compared to current human efforts at travel and exploration and the near term future extremely limited prospects for settlement off world, it seems more a matter of time and numbers again. Given enough time and enough civilizations, one would expect there to be some signs. Since there aren’t, it seems there aren’t any others or very few or none have had enough time. That seems paradoxical given the usual starting assumptions. (And those assumptions don’t seem unreasonable.)

The usual discussion about this stuff proceeds along the lines of there being done filter that makes spacefaring civilizations very unlikely — like life is really hard to get in the first place or civilizations tend to self-destruct when they inevitably invent X. None of these seems satisfying for most.

Regards,

Dan