The thing about SETI (and any other alien civ detector) is that it has finite resources. It can't look for everything so it has to prioritise things we know intelligent species produce that can be detected, like radio waves. Beyond that we could look for things that are reasonable speculation like matrioshkas.
Anything beyond that is anyone's guess. Dark matter could be some exotic matter intergalactic civilisation for all we know but how we'd determine that at the moment is unclear.
Also I agree with Bear. From an evolutionary perspective I have a hard time seeing how intelligent life (of our standard) would be common, there's little reason such life couldn't have evolved on Earth at any point within the last few hundred million years, but there's no evidence it did.
Anything beyond that is anyone's guess. Dark matter could be some exotic matter intergalactic civilisation for all we know but how we'd determine that at the moment is unclear.
Also I agree with Bear. From an evolutionary perspective I have a hard time seeing how intelligent life (of our standard) would be common, there's little reason such life couldn't have evolved on Earth at any point within the last few hundred million years, but there's no evidence it did.
OA Wish list:
- DNI
- Internal medical system
- A dormbot, because domestic chores suck!