The Fermi Paradox

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Stuvian
Posts: 1
Joined: Thu Mar 07, 2013 8:30 pm

The Fermi Paradox

Post by Stuvian »

Hi Physics Forum,
Read this interesting take on the human search for life outside our own solar system. Created by an Italian physicist, Enrico Fermi (shared father of the atomic bomb with Robert Oppenheimer), his paradox states...

"The Fermi paradox is a conflict between an argument of scale and probability and a lack of evidence. A more complete definition could be stated thus:
The apparent size and age of the universe suggest that many technologically advanced extraterrestrial civilizations ought to exist.
However, this hypothesis seems inconsistent with the lack of observational evidence to support it."

Just thought this was a cool theory that has interesting implications for humans... Any thoughts? Is Fermi wrong? Is there a better approach? Does it really matter?

Thanks

P.S: there is a very cool piece of estimation on this wiki page that won't fit in the post...

Source: http://en.wikipedia.org/wiki/Fermi_paradox
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joe
Posts: 755
Joined: Fri Aug 29, 2003 11:57 am
Location: Sydney

Re: The Fermi Paradox

Post by joe »

Great, isn't it? Fermi was brilliant at what we now call a Fermi problem: getting an order-of-magnitude answer to a problem quickly from first principles. I hope that, during this course, you'll enjoy some Fermi problems.

The Fermi paradox suggest that intelligent, colonising life is either *extremely* rare in the universe or lasts only briefly. We can't extrapolate from small samples (especially a sample of 1!) but we might note:

Substantially technological species has evolved on earth only once (in Africa): mammals had plenty of time on most continents, but still no technological kangaroos, llamas etc. It's not inevitable. So, even if life is not extremely rare, technological life may be.

Brevity? Will we last long enough and preserve earth's resources well enough to colonise other star systems? Will we produce a global catastrophe that stops luxuries like space programs?

If the Fermi paradox means that advanced life is astonishingly rare and perhaps brief, it's another reason to look after it.

Joe
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