3 ms·

Because that's what we have today, so that's what they have to work with. It's a shot in the dark in the hope that we might be able to find a remnant sign. If

Because that's what we have today, so that's what they have to work with. It's a shot in the dark in the hope that we might be able to find a remnant sign. If we detect radio signals in another galaxy but FTL is impossible who cares? The human species will be extinct before any interaction can occur. It's probable that whatever species sent them is already extinct because it's at least 3 billion years old. If c is the ultimate speed limit there's really no point in looking anywhere else because everything else is so far away it's irrelevant.

int_19h 8y ago
Knowledge doesn't need to have a practical purpose to be satisfying.
canhascodez 8y ago
The problem is that you can either have FTL or causality, but not both. Also, relativity has been extremely accurate as a description of the universe, particularly on the macro level that you and I happen to inhabit. I'd say that I'd never bet on FTL being real, but to be honest I'd be surprised if you ever found anyone to even lay you odds. And as you say, that does make SETI rather pointless even without considering that the SNR to Mars on a good day is, what, ~11 dB? We get generation ships, and if we are extremely lucky, we may have some very patient pen-pals, but warp drives, ansibles, and their attendant paradoxes are pretty unlikely to be features of this universe. Personally I prefer a knowable universe to a tourable one.
hannasanarion 8y ago
So you're saying we should shut down all of the large and Radio and space telescopes, because it's pointless to look at things you can't visit?
- themagician 8y ago
  Not just visit, anything. You'd never be able to communicate. The SNR is such that it would always just be noise. If FTL isn't possible then the end result of listening is simply the confirmation that something else exists and it stops right there.
  - hannasanarion 8y ago
    Conversation isn't the only thing you can do with messages. Alan Turing didn't crack Enigma so that he could have a lovely chat with the Germans. Don't you think there's at least a little bit that could be learned by listening to alien communications from centuries ago, other than the fact that it exists? If such signals were found, would you really stop reading at the headline "alien communication discovered"?

int_19h 8y ago

Knowledge doesn't need to have a practical purpose to be satisfying.

canhascodez 8y ago

The problem is that you can either have FTL or causality, but not both. Also, relativity has been extremely accurate as a description of the universe, particularly on the macro level that you and I happen to inhabit. I'd say that I'd never bet on FTL being real, but to be honest I'd be surprised if you ever found anyone to even lay you odds. And as you say, that does make SETI rather pointless even without considering that the SNR to Mars on a good day is, what, ~11 dB? We get generation ships, and if we are extremely lucky, we may have some very patient pen-pals, but warp drives, ansibles, and their attendant paradoxes are pretty unlikely to be features of this universe. Personally I prefer a knowable universe to a tourable one.

hannasanarion 8y ago

So you're saying we should shut down all of the large and Radio and space telescopes, because it's pointless to look at things you can't visit?

themagician 8y ago
Not just visit, anything. You'd never be able to communicate. The SNR is such that it would always just be noise. If FTL isn't possible then the end result of listening is simply the confirmation that something else exists and it stops right there.
- hannasanarion 8y ago
  Conversation isn't the only thing you can do with messages. Alan Turing didn't crack Enigma so that he could have a lovely chat with the Germans. Don't you think there's at least a little bit that could be learned by listening to alien communications from centuries ago, other than the fact that it exists? If such signals were found, would you really stop reading at the headline "alien communication discovered"?