From the NOVA PBS series "THE ELEGANT UNIVERSE', host Brian Greene guides us through Einstein's explanation of gravity.
Brian Greene is a theoretical physicist and one of the best-known string theorists. Since 1996 he has been a professor at Columbia University.
The Elegant Universe was adapted for a three hour program in three parts for television broadcast in late 2003 on the PBS series NOVA.
http://www.pbs.org/wgbh/nova/elegant/
