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The other resolution to Fermi's paradox is much simpler and much less interesting. Maybe interstellar travel is as difficult as all our scientists tell us it is

The other resolution to Fermi's paradox is much simpler and much less interesting. Maybe interstellar travel is as difficult as all our scientists tell us it is. No civilization has colonized the Galaxy because it's simply too difficult. Maybe FTL travel really is impossible. Maybe SETI hasn't detected anything because generating a signal loud enough for us to detect is a stupendous amount of energy, and it's simply too much energy for a single planet civilization to justify using on a radio transmission that's going to travel at most a quarter of the way across their star system. Maybe all the science fiction we love so much really is just fiction.

ubercore 8y ago
Even without FTL travel, on galactic timelines, we could presume to see colonization spread very rapidly through the galaxy. For example, this answer on quora shows with some pretty conservative timelines, the galaxy should still be riddled with life: https://www.quora.com/Could-the-answer-to-the-Fermi-paradox-be-that-travelling-faster-than-light-is-just-not-possible-If-you-have-to-spend-500-000-years-traveling-to-Earth-your-ships-would-have-to-be-extremely-comfortable-Why-would-you https://www.quora.com/Could-the-answer-to-the-Fermi-paradox-...
- mcbits 8y ago
  Those timelines don't seem very conservative. 1% sounds like a nice, small number, but 1% of the speed of light is insanely fast. It's about 200 times faster than our fastest craft to date. We might envision launching a probe 200 times faster in the future, but a colonization ship would also weigh millions of times more and have to slow down somehow. It's not clear that we'd be able to do that in 10,000 years (or ever) with "shoot stuff out the butt" propulsion, so we'd probably need propulsion based on different physics which may or may not actually exist. We'd definitely need new physics for constant 1g acceleration into relativistic speeds. Maybe we could hitchhike on progressively faster interstellar asteroids or something, but that would void the assumption of having the ability to reach all parts of the galaxy.
- pixl97 8y ago
  Eh, the slow travel still has lots of issues. You have to travel with a massive amount of mass. Space is really dangerous. There are high energy particles that want to mess up your 'ship'. Even worse things like neutral hydrogen are hard to block with energy style shields. Then you have the issues of long times without high gravity. Then you have to carry enough 'stuff' and energy to recycle absolutely everything you need, ever.
clubm8 8y ago
>Maybe SETI hasn't detected anything because generating a signal loud enough for us to detect is a stupendous amount of energy, and it's simply too much energy for a single planet civilization to justify using on a radio transmission that's going to travel at most a quarter of the way across their star system. Plus even if you can do something doesn't mean you should https://en.wikipedia.org/wiki/Fermi_paradox#It_is_dangerous_to_communicate https://en.wikipedia.org/wiki/Fermi_paradox#It_is_dangerous_...

ubercore 8y ago

Even without FTL travel, on galactic timelines, we could presume to see colonization spread very rapidly through the galaxy. For example, this answer on quora shows with some pretty conservative timelines, the galaxy should still be riddled with life: https://www.quora.com/Could-the-answer-to-the-Fermi-paradox-be-that-travelling-faster-than-light-is-just-not-possible-If-you-have-to-spend-500-000-years-traveling-to-Earth-your-ships-would-have-to-be-extremely-comfortable-Why-would-you https://www.quora.com/Could-the-answer-to-the-Fermi-paradox-...

mcbits 8y ago
Those timelines don't seem very conservative. 1% sounds like a nice, small number, but 1% of the speed of light is insanely fast. It's about 200 times faster than our fastest craft to date. We might envision launching a probe 200 times faster in the future, but a colonization ship would also weigh millions of times more and have to slow down somehow. It's not clear that we'd be able to do that in 10,000 years (or ever) with "shoot stuff out the butt" propulsion, so we'd probably need propulsion based on different physics which may or may not actually exist. We'd definitely need new physics for constant 1g acceleration into relativistic speeds. Maybe we could hitchhike on progressively faster interstellar asteroids or something, but that would void the assumption of having the ability to reach all parts of the galaxy.
pixl97 8y ago
Eh, the slow travel still has lots of issues. You have to travel with a massive amount of mass. Space is really dangerous. There are high energy particles that want to mess up your 'ship'. Even worse things like neutral hydrogen are hard to block with energy style shields. Then you have the issues of long times without high gravity. Then you have to carry enough 'stuff' and energy to recycle absolutely everything you need, ever.

clubm8 8y ago

>Maybe SETI hasn't detected anything because generating a signal loud enough for us to detect is a stupendous amount of energy, and it's simply too much energy for a single planet civilization to justify using on a radio transmission that's going to travel at most a quarter of the way across their star system. Plus even if you can do something doesn't mean you should https://en.wikipedia.org/wiki/Fermi_paradox#It_is_dangerous_to_communicate https://en.wikipedia.org/wiki/Fermi_paradox#It_is_dangerous_...