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- Are we inside a black hole? 8 answers
In "The Physics of Star Trek" by Lawrence M. Krauss, he mentions that our universe, by all calculations, should actually be a black hole. I read it a while ago, but I think he mentioned that the mass in our (observable) universe is higher than the size of it, to the point where the observable universe is smaller than the Schwarzschild radius. If that is correct, then our universe should collapse into a singularity. Maybe I don't remember it correctly, or the problem is that we do not "see" the actual size of the universe, but only a small part (however, due to the homogenicity of it all, the density would be the same).
My question is if Krauss is correct in what he says (assuming I remember correctly), and if there is a reference to the original paper?