Sharp BlueRichard Baker's thoughts on history, science, technology, literature and the future.The causal structure of black holes, part one- April 15, 2008 A commenter writing about my earlier post, "Relativity, FTL and Causality" said: As far as FTL being equivalent to time travel, the above explanation is correct. As far as FTL being impossible at present, it is not quite. Richard's explanation lacks a mention of black holes. An object (with non-zero mass), falling into a black hole from rest, will cross the event horizon AT THE SPEED OF LIGHT. Unfortunately we (the distant observers) would not be able to witness this event, since the falling...http://www.theculture.org/rich/sharpblue/archives/000189.html |