Time travel has long been a topic of science fiction, filled with thrilling possibilities and mind-bending problems. The most famous of these problems is the "grandfather paradox".

David Nield Fri, November 15, 2024, 5:18 PM PST 3 min read A physicist has worked out the math that makes 'paradox-free' time travel plausible ...

The idea of a particle that races faster than light has long fascinated physicists. Known as the tachyon, it was originally dreamed up to help untangle paradoxes in quantum theory and relativity ...

The idea is that space-time itself holds a history of quantum information in “memory cells.” This is just one of many hypotheses that aim to explain the paradoxes that form when general ...