[ Astronomy & Space ] Open Question : How do we know we are not inside a black hole?
Things like the Big Bang, dark matter/energy, dual-slit experiments, and identical twins experiments all seem to point to the conclusion that the Universe is enclosed inside a black hole. Is there any evidence that this is NOT the case? It just seems to make a lot of sense that the Universe is an infinitely dense point expanding into an infinitely curved space. Since everything in the Universe would be in contact with everything else, as well as with the surface of the black hole, in-falling material may be close enough to be sensed before it is incorporated into the black hole/our Universe -- hence "dark energy." The addition of this material to our black hole would also explain the increase in the rate of the Universe's expansion.
Source: http://answers.yahoo.com/question/index?qid=20110306155917AAlVdt0