One of the most awkward parts of writing a book is that, eventually, authors have to ask people for “blurbs” – the endorsements that you see on the cover of a book, encouraging you to buy it. I am now ...

Einstein's theory of general relativity views time similarly to width, height, and length. As such, both time and space can be curved by gravity. This effectively means that time is slower the closer ...

Follow the space program since the moon landing in the four-part documentary "Once Upon a Time in Space". Here’s how to watch it anywhere on the planet. When you purchase through links on our site, we ...

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 ...

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 ...

Intuitively, we know what time is, but try to explain it, and we end up tying our minds in knots. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works.

For more than a century, physics has treated space and time as the smooth stage on which the universe unfolds, a flexible fabric that bends but never breaks. A new wave of theories is now challenging ...