Is TIME TRAVEL possible? If we believe certain versions of the view that the universe consists of curved space-time, the answer is yes. In the second election of his A Brief History & Time, Stephen Hawking developed the idea, first mooted by Einstein in 1935, that it might be possible to visit different eras in the universe's history by passing through channels, known as 'wormholes', connecting space-time regions whose curvature bends them close together.
Hawking also considered the question of why we have so far had no visitors from the future. It is, he said, because either space-time does not have the right kind of curvature after al. or it will only attain it ii the future. so that only in the future can