Another Take on Fermi's Paradox (aliens)

[Vasily]

Fermi's Paradox: a spacefaring civilization should have spread throughout the galaxy by now. Where are they? A lot of solutions have been suggested -- this one, based on computer simulation, suggests the aliens aren't here because we're living in the equivalent of a trailer park in the woods way off the interstate. "What about that star system, Zeke?" "Nah, that's off in the boonies. T'ain't worth the gasoline. Stick to the highways. Maybe on our next vacation."

This is probably the best article I've read on the issues involved.

https://www.scientificamerican.com/a...wded-milky-way

The article also points out that if we *have* been visited by aliens in the distant past, or they even had a colony here, we'd likely see no evidence of it.

As fantastic as it may seem, Schmidt and Frank argue—as do most planetary scientists—that it is actually very easy for time to erase essentially all signs of technological life on Earth. The only real evidence after a million or more years would boil down to isotopic or chemical stratigraphic anomalies—odd features such as synthetic molecules, plastics or radioactive fallout. Fossil remains and other paleontological markers are so rare and so contingent on special conditions of formation that they might not tell us anything in this case.

[fisheye]

We do not have all the answers and it is hard to tell if any other civilizations have those answers. We have been looking for dark matter and we have many theories where it is and what to look for; but we really don't know: https://www.discovermagazine.com/the...f-a-spacecraft. I quote: "The deeper question is why dark matter is so diffuse, while visible matter clumps together conveniently into dense things like stars and planets. Nobody has detected dark matter directly, so there is no definitive answer to that question."

What I am saying is that we don't know what is in the deep space between solar systems and galaxies. It is only speculation at this point in time. I have to presume that our first attempts into the far reaches of space will be with AI and not human astronauts. However, like pointed out indirectly in your link; our civilization might no longer exist by the time we would get meaningful information about distant, inhabitable, planets?

[Vasily]

Originally Posted by fisheye

What I am saying is that we don't know what is in the deep space between solar systems and galaxies. It is only speculation at this point in time. I have to presume that our first attempts into the far reaches of space will be with AI and not human astronauts.

I think that's likely, too -- they're talking about sending micro probes to Alpha Centauri.

However, like pointed out indirectly in your link; our civilization might no longer exist by the time we would get meaningful information about distant, inhabitable, planets?

I keep a list of civilization killers that I update when I read about a new one (or think of one myself). It keeps getting longer. I just added item #5 based on this article

1. Supervolcano eruption - Yellowstone
2. Extended period of volcanism like those that created the Deccan Traps
3. Climate change, man-made or natural
4. Another ice age due to solar changes or passage through galactic dust clouds
5. Passage through bands of galactic dark matter leading to mass extinction events
6. Major asteroid or comet impact
7. Magnetic pole flip
8. Pathogen mutation natural or man-made - unstoppable killer bug
9. Alien pathogen brought to earth by panspermia or sample returns
10. Massive crop failure due to pathogen + lack of genetic diversity
11. Ecosystem instabilities due to reduced diversity (extinctions)
12. Massive solar flare like the one in 1850
13. Gamma ray burst from a nearby star
14. Nearby supernova
15. Oort cloud disruption by unseen solar companion raining comets on us
16. Nuclear war
17. Unforeseen effects of nanotechnology or artificial intelligence
18. Vacuum decay causing a bubble of true vacuum to expand, destroying everything

Rather depressing ...

[fisheye]

Number 16 should be number 1 this week. The Doomesday Clock is still only 2 minutes before midnight and it might have even edged closer. I really do not like this push for faster warheads that it seems all the superpowers are researching them right now.