The universe comes with a built‑in speed cap, a hard limit that shapes everything from how stars shine to how cause and effect unfold. That limit is usually described as the speed of light, yet the ...

IT IS ONE of the biggest mysteries in cosmology—and getting bigger all the time. Ever since Edwin Hubble, an American astronomer, published observations of distant galaxies in 1929, scientists have ...

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 ...