The speed of light is the fastest anything can travel. What happens to a photon from a galaxy 25 million light years away on its journey toward Earth?

It seems there isn’t a sci-fi part if the universe in which everything is made of antimatter.

Your experience of time is relative because it depends on motion – more specifically, your speed and acceleration.

The theory of gravity may need to be altered.

Physicists know a lot about the most fundamental properties of the universe, but they certainly don’t know everything. 2021 was a big year for physics – what was learned and what’s coming next?

Such a mission could be developed soon, allowing astrophysicists to take selfies of the solar system and use the Sun’s gravity as a lens to peer deep into space.

Gravity is something every person on Earth intuitively understands: It is what keeps you on the ground. But how come gravity pulls down, rather than pushes up? Einstein came up with the answer.

If humanity wants to travel between stars, people are going to need to travel faster than light. New research suggests that it might be possible to build warp drives and beat the galactic speed limit.

Calculations show that wormholes should create a spectacular display of gamma rays that we could try to observe.

Field theory describes the universe as energy flowing along unending lines. With this perspective, it is possible to define a new fundamental building block of matter.