While some contend that there could exist extraterrestrial civilizations that have been around for a billion years and therefore a billion years more advanced than us, others stand by the Fermi Paradox which asserts if they were out there we would have heard from them.
If there are old civilizations out there, I wonder what one billion year generation iPhones look like.
Fermi reasoned, if there are other advanced extraterrestrial civilizations, then why is there no evidence of such, like spacecraft or probes floating around the Milky Way. His question became famously known as the Fermi Paradox. The paradox is the contradiction between the high estimates of the probability of the existence of extraterrestrial civilizations and yet the lack of evidence for, or contact with, any such civilizations.
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Not only don't we have the technology the ET's would use, we can't even IMAGINE that technology.
Hopefully that will happen before nanotech weapons arrive because that really will be the end of the world. Nuclear weapons will be paintball guns in comparison.
However, I'd like to believe that there are hundreds to thousands of civilizations that have been or still are in our galaxy alone. It's a pretty easy thing to believe.
To see evidence of another civiliztion that has interstellar travel we would have to be looking in the right direction, with the device properly focused, at the right time. And then you'd have to realize that whatever you are seeing is a snapshot of something that happened long long ago.
And maybe they haven't come here because humankind is still too wrapped up in our own petty differences to be worth the time.
Think of all the craziness that would ensue by all the conspiracy nutballs if aliens actually made themselves known to us.
Sad to say, but as a race, humans aren't ready to be visited by a race that has the ability to travel here. Maybe someday....
consciousness is unable to engage in reflection.
It is carried along by its own decline
and it continues to lay hold of images indefinitely.
- Jean-Paul Sartre
I love these guys.
Time travel messes it up, so thats of the table :)
that or the advanced aliens are playing us like a bad game of simworld.
Technologically speaking, we're not really advanced beyond imaginary friends, better ways to masturbate, and/or faster ways to kill each other. We can't even recreate the great pyramids of Giza which were built long before our "great society."
Why would an advanced civilization want to come here at all?
Land. Resources. Human slaves. Accident...
My other take on the issue is that we are measuring these things by our own time span, what if the such lifeforms were born, grown and died in days, yet still found a way to conciousness and their evolutionary zenith? Maybe they have come and gone, there are no gaps, because there is no parallel to us.
There is a possibility that the galaxy is the equivalent of a forest at night and we are something small and young squeaking away in the open when we should be hiding under a log until we know what we might find out there.....