time travel
This issue of Plus is a special, marking the occasion of Stephen Hawking's
60th birthday. Plus attended his
Birthday Conference in
Cambridge, where
we interviewed some of the world's most influential mathematicians and
physicists.
Tags: gravity : cosmology : curvature of space : Grand Unified Theory : black hole : Big Bang : quantum mechanics : general relativity : relativity : time travel : wormhole

Take a journey to the limits of common sense
Tags: theoretical physics : physics : quantum mechanics : time travel

Mathematicians give green light for time machine
Tags: physics : general relativity : special relativity : time dilation : relativity : time travel