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 ...

Comet 3I/ATLAS is the third known interstellar comet after 2017's 1I/'Oumuamua and 2019's 2I/Borisov. It was discovered on ...

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 ...

Albert Einstein's general theory of relativity describes gravity as the warping of space-time geometry by mass, a concept distinct from Isaac Newton's absolute space and time, and has been empirically ...

Two blind spots torture physicists: the birth of the universe and the center of a black hole. The former may feel like a moment in time and the latter a point in space, but in both cases the normally ...

If you wave your hand in front of your face, you won’t notice anything particularly interesting. Perhaps a gentle waft of air against your cheek – that’s about it. No epiphany. No major sign that ...

Black holes are often considered terrors of the known universe. Supermassive black holes are regions of space where the pull of gravity is so intense that even light doesn't have enough energy to ...