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 ...

Whether space-time exists should neither be controversial nor even conceptually challenging, given the definitions of “space-time,” “events” and “instants.” The id ...

We all need some space sometimes—but it's harder to find than you might think. How far into our universe do we have to go to ...