If we do discover a complete theory, it should be in time understandable in broad principle by everyone. Then we shall all, philosophers, scientists, and just ordinary people be able to take part in the discussion of why we and the universe exist. – Stephen Hawking
Time travel used to be thought of as just science fiction, but Einsteins general theory of relativity allows for the possibility that we could warp space-time so much that you could go off in a rocket and return before you set out. – Stephen Hawking