The speed of light is the ultimate limit of motion, yet against the vast scale of the cosmos it becomes painfully inadequate.

When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. Light travels at 186,000 miles per second (300 million meters per second) and is believed to set ...

In this video I show you what it would look like to slow the speed of light down to around walking speed. So with just ...

A tiny optical device built into a silicon chip has achieved the slowest light propagation on a chip to date, reducing the speed of light by a factor of 1,200 in a study reported in Nature Photonics ...

Einstein’s claim that the speed of light is constant has survived more than a century of scrutiny—but scientists are still daring to test it. Some theories of quantum gravity suggest light might ...

If there is an absolute law in the universe, it’s that nothing can travel faster than the speed of light. For science-fiction enthusiasts, that’s a bit depressing. Space is big, and while the speed of ...