: : Black holes with an event horizon the size of our universe : : would have a low density within the event horizon and thus : : we could be living in a giant black hole. If the space time : : event horizon is in expansion from the big bang but with : : a residual massive black hole equating the event horizon : : computation equal to the size of the universe; the universe : : would appear as it does to us today. : : Comments

: Well, for starters I would mention a few things...

: First, I don't perceive that the cosmos we are currently inhabiting possess the qualities of the inside of a EH. The assumptions I made above could lead to a universe similar to ours.

: The idea of an EH is such that it is merely a boundary where spacetime is infalling at a velocity infinitely close to 'c'. : In all actuality, the "space" beyond the EH is nothingness. There is no dimensional characteristics beyond an EH; hence there is no spacetime continuum. There are more schools of thought about what lies on the other side of the boundary (read some of Jean-Peierre Luminet ideas - a French black hole specialist). A black hole requires the existence of a regions of space-time outside the hole to which nothing inside can escape.

Also John Gribbins from Cambridge claims we could be living in a giant black hole and not even notice. The density of a spherical black hole is approx = (3c^6)/(32*pi(G^3)*M^2) by combining equations for the density of a sphere with the Schwarzschild radius. This density is very very low for an estimated mass >= to our universe.

• Re: Event horizon the size of our universe - nåte - March 19, 1999 - 03:36 UTC