One of the most famous paradoxes ever, the grandfather paradox, cautions against making changes that could break the timeline if you were to ever travel back in time. But, according to one scientist, ...

Like stretch marks left on skin that expanded too quickly or cracks embedded in freezing ice, cosmic strings are artifacts of what the universe looked like in the moments before it rapidly changed ...

The grandfather paradox is just one of the thorny logical problems that arise with the concept of time travel. But one physicist says he has resolved them.

Does the science in the time travel movies that we love actually make sense? As Back to the Future, arguably the greatest time travel movie in history, turns 40, BBC Radio 4's Screenshot is ...