Comment by echelon
3 days ago
Speaking of "great filter", I often wonder about the hypothetical case that we live in a fragile universe.
Whatever the first civilization is to cause something like vacuum collapse could destroy the entire universe at the speed of light. Maybe it's already happened somewhere and is currently propagating our way.
Maybe it even is happening but will never reach us from their local observable sphere.
Guess it's good that space expands faster than the speed of light.
if you haven't read Schild's ladder, you're in for a treat :-D