This puzzle is known as the problem of time, and it remains one of the most persistent obstacles to a unified theory of physics. Despite enormous progress in cosmology and particle physics, we still ...

Gravity used to be the most dependable rule in the cosmic rulebook, the quiet background force that never changed its mind. Now a series of discoveries and bold claims are turning that certainty into ...

An astrophysicist explains what wormholes are and how these theoretical space-time tunnels have popped up in the solutions to a set of decadesold equations.

UK-based Space Forge wants to create ultra-high-quality crystals in space for the manufacture of semiconductors back on Earth.