4 ms·

If FTL is possible (and engineerable) then the Fermi paradox becomes a serious problem. There "should" be aliens all over the place unless... (1) We are wrong

by api 5y ago

If FTL is possible (and engineerable) then the Fermi paradox becomes a serious problem. There "should" be aliens all over the place unless... (1) We are wrong about the nature of the universe and strong theism / creationism or the simulation hypothesis (which is the same thing more or less) are right. (2) Life or complex life are so phenomenally unlikely that we are literally the only example in the local galactic supercluster at least, if not the whole universe. Speaking of creationists they often argue that the probability of life forming from non-life is insanely low. Maybe they're right about those probabilities and it only happened once. (3) We live in a cosmic cemetery. There is a big nasty great filter ahead of us, and nobody has passed so far. Maybe the great filter is when you try to actually build FTL and cause a space-time catastrophe. (4) We live in a "dark forest" and should be very, very quiet. Shhhhh.... (5) We live in a nature preserve. See #6. (6) Last but not least, at least some UFOs really are ETs in which case there is no Fermi paradox. They're here and we have seen them. They're just laying low and not making overt contact. My money would be on 6. If we demonstrated some kind of engineerable FTL I'd take the possibility that at least a few UFOs are ETs very seriously.

postalrat 5y ago
Fermi's paradox does not depend on FTL travel.
- api 5y ago
  No, but the difficulties of conventional interstellar travel provide some cushion in any model. If you can build a USS Enterprise that cushion goes away.
anonydsfsfs 5y ago
Or 7) FTL is possible, but the amount of energy required is so insanely large it doesn't matter. The paper says it takes energy equivalent to "four orders of magnitude smaller than the solar mass", which is an absurd amount. This reminds of an interview I read with Donald Knuth about the P vs. NP problem. IIRC, Knuth said he believes there probably is a polynomial time algorithm to solve NP problems, but the constant factor will be so absurdly huge (e.g. Graham's number) that it could never be run on an actual computer. I've heard layman claim that if P=NP were proven, then it'd suddenly spell the end of encryption relying on NP problems, but it's entirely possible that it'd have no practical impact. The constant factor is analogous to energy requirements for FTL.
- api 5y ago
  That’s why I said engineerable. If it takes the mass-energy of Jupiter it’s likely something that could never be done since no material could contain or control such energy in an organized way. This paper does not offer an engineerable solution but it does argue that negative mass, which may not exist, may not be required. That brings us closer. Are there solutions that require less energy? Are they physical or just math artifacts? Get the energy down to LHC levels and it becomes testable if even at submicroscopic scale. Show it at any scale and it’s a physics revolution and front page news and loads of money starts being spent. Going to the moon was once dismissed by many scientists as requiring silly amounts of energy until we figured out a bunch of things like modern rocket engines and staged rockets.

by api 5y ago

postalrat 5y ago

Fermi's paradox does not depend on FTL travel.

api 5y ago
No, but the difficulties of conventional interstellar travel provide some cushion in any model. If you can build a USS Enterprise that cushion goes away.

anonydsfsfs 5y ago

Or 7) FTL is possible, but the amount of energy required is so insanely large it doesn't matter. The paper says it takes energy equivalent to "four orders of magnitude smaller than the solar mass", which is an absurd amount. This reminds of an interview I read with Donald Knuth about the P vs. NP problem. IIRC, Knuth said he believes there probably is a polynomial time algorithm to solve NP problems, but the constant factor will be so absurdly huge (e.g. Graham's number) that it could never be run on an actual computer. I've heard layman claim that if P=NP were proven, then it'd suddenly spell the end of encryption relying on NP problems, but it's entirely possible that it'd have no practical impact. The constant factor is analogous to energy requirements for FTL.

api 5y ago
That’s why I said engineerable. If it takes the mass-energy of Jupiter it’s likely something that could never be done since no material could contain or control such energy in an organized way. This paper does not offer an engineerable solution but it does argue that negative mass, which may not exist, may not be required. That brings us closer. Are there solutions that require less energy? Are they physical or just math artifacts? Get the energy down to LHC levels and it becomes testable if even at submicroscopic scale. Show it at any scale and it’s a physics revolution and front page news and loads of money starts being spent. Going to the moon was once dismissed by many scientists as requiring silly amounts of energy until we figured out a bunch of things like modern rocket engines and staged rockets.