The fact that true vacuum propagates at the speed of light is especially terrifying, because given the sheer size of the universe, it means this process might have been happening for a billion years already and just hasn't reached us yet!
In fact... isn't there a big, unexplained black spot on the background radiation map? Could that be true vacuum propagating? Could we already be doomed?
This was cross-posted from https://fayanora.dreamwidth.org/1442784.html
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