Oftentimes, we think of space as an endless, mostly empty vacuum, a silent backdrop where planets, stars, and galaxies play out their dance. We also think of time as something separate, a steady ...

Time is the strange dimension: Unlike its spatial siblings, it is a one-way street as the clock only ever ticks forward and never backward. Scientists have long been aware of time's quirks, with the ...

Physicists hope that understanding the churning region near singularities might help them reconcile gravity and quantum mechanics. At the beginning of time and the center of every black hole lies a ...

Whether space-time exists should neither be controversial nor even conceptually challenging, given the definitions of “space-time,” “events” and “instants.” The idea that space-time exists is no more ...

A clear introduction to how space and time are studied in physics, and how they shape motion, gravity, and the structure of the universe.