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# quantum physics

## Latest Articles

### Imaginary Numbers May Be Essential for Describing Reality

A new thought experiment indicates that quantum mechanics doesn’t work without strange numbers that turn negative when squared.

### Decades-Long Quest Reveals Details of the Proton’s Inner Antimatter

Twenty years ago, physicists set out to investigate a mysterious asymmetry in the proton’s interior. Their results, published today, show how antimatter helps stabilize every atom’s core.

### A New Theorem Maps Out the Limits of Quantum Physics

The result highlights a fundamental tension: Either the rules of quantum mechanics don’t always apply, or at least one basic assumption about reality must be wrong.

### What Is a Particle?

It has been thought of as many things: a pointlike object, an excitation of a field, a speck of pure math that has cut into reality. But never has physicists’ conception of a particle changed more than it is changing now.

### The Most Famous Paradox in Physics Nears Its End

In a landmark series of calculations, physicists have proved that black holes can shed information.

### A New Map of All the Particles and Forces

We’ve created a new way to explore the fundamental constituents of the universe.

### Quantum Tunnels Show How Particles Can Break the Speed of Light

Recent experiments show that particles should be able to go faster than light when they quantum mechanically “tunnel” through walls.

### The Mathematical Structure of Particle Collisions Comes Into View

Physicists have identified an algebraic structure underlying the messy mathematics of particle collisions. Some hope it will lead to a more elegant theory of the natural world.

### Why Gravity Is Not Like the Other Forces

We asked four physicists why gravity stands out among the forces of nature. We got four different answers.