Stephen Hawking on Time Travel: The Hidden Science Behind Warping Space-Time

„Since we can’t change the way the universe began, the question of whether time travel is possible is one of whether we can subsequently make space–time so warped that one can go back to the past. I think this is an important subject for research, but one has to be careful not to be labelled a crank. If one made a research grant application to work on time travel it would be dismissed immediately. No government agency could afford to be seen to be spending public money on anything as way out as time travel. Instead one has to use technical terms like closed time-like curves, which are code for time travel. Yet it is a very serious question.“