Redefining Reality - The Intellectual Implications of Modern Science

Surrounding the black hole is a border called the ;
anything that crosses it cannot reemerge.
An unfortunate traveler would have no sense that he or she
had crossed the event horizon, but anyone watching would
experience something peculiar.
Remember that special relativity includes an effect called time
dilation, according to which time slows down when measured
by a fast-moving observer. Because of time dilation and the
curvature of space-time, a traveler would appear to move
slower the closer he or she got to the black hole to an outside
observer. Right around the event horizon, time would appear to
stop for the observer.
Physicists came to realize that the solutions to Einstein’s equations
that yielded black holes predicted that at the center there would
be a . The problem is that the curvature of the space is
measured as a 1/x term, and if we treat objects as point masses, then
the x term goes to 0. Here is a result of the equations of general
relativity—1/0—that cannot be connected to reality. Einstein’s
theory of general relativity seems to describe a reality that cannot
be real.
Einstein, , part II.
Gedroch, .
Thorne, Black Holes and Time Warps, chapter 2.
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