Stephen Hawking Is Terrified Of An Alien Invasion, And The Reason Makes Nothing But Sense

[krispos42]

66. There's a good argument to make that there are damn few intelligent races in the universe...

...and that we might be the only one in the Galaxy.


The Fermi Paradox.... if our star is an average star, and our planet an average planet, then, given the lifespan of the universe, any civilization out there has had more than enough time to spread to Earth. So... where are they?

Basically, if goes that if intelligent life is common... humanity shouldn't be here. Aliens from however many thousands of light-years away have had millions or billions of years to get here, so given the time frame, they would have eventually found Earth and colonized us somehow.

Maybe frozen embryos in a space ship that lands here and grows the first generation in artificial wombs. They would be raised by computers and robots, at least the first generation, and then proceed to mate normally and fill the planet.

Maybe a shipload of colonists in cold sleep. Maybe a multi-generational ship. Or maybe they simply use the time-dilation effect of near-light-speed travel to travel vast distances in relative months.


Regardless of the method, they should be here already!

The fact that they aren't might mean that intelligent life occurs only once per galaxy... or maybe even less often.

We might be the only intelligent species for a million light-years.


It would only take a few million years for one planet to spread intelligent life throughout our Galaxy; our planet has been inhabitable for dozens of times that. So... where is everybody???

http://en.wikipedia.org/wiki/Fermi_paradox