Tachyons, faster-than-light particles, challenge Einstein's theory, hinting at time travel. New models suggest they may reshape physics, causality, and cosmic expansion.

A theoretical particle that travels faster than light, the tachyon has long intrigued physicists and fueled decades of speculation. Initially conceived as a possible solution to quantum and relativity ...

According to Einstein’s theory, simultaneous events in one ... This is because it takes time for the light to travel. So when the train is in motion, the light will have to cover that extra ...

Euclid’s jaw-dropping capture of the closest Einstein ring ever seen reveals the hidden forces shaping our universe — and ...

Euclid space telescope sent some images back to Earth during an early testing phase. While reviewing the pictures, astronomer ...

Like stretch marks left on skin that expanded too quickly or cracks embedded in freezing ice, cosmic strings are artifacts of what the universe looked like in the moments before it rapidly changed ...

Euclid, a space telescope on a mission to uncover the secrets of dark matter and dark energy, has already made a stunning discovery: a perfectly formed Einstein ring hidden in a well-known galaxy.

The theory is a series of equations defined by Einstein. These equations combine space and time to create space-time. Gravity is explained by these equations, which are consistent with what we see ...

Einstein’s ... the theory of relativity is the nature and behavior of light. In the 19th century, the prevailing idea was that light is a wave motion, and therefore needs a medium to travel ...