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theoretical physics

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particle physics

‘Last Hope’ Experiment Finds Evidence for Unknown Particles

April 7, 2021

Today’s long-anticipated announcement by Fermilab’s Muon g-2 team appears to solidify a tantalizing conflict between nature and theory. But a separate calculation, published at the same time, has clouded the picture.

Orange hills (polaritons) against a black background. Below each hill, an arrow points to an angular position on a circle.
explainers

The Near-Magical Mystery of Quasiparticles

March 24, 2021

The zoo of spontaneously emerging particlelike entities known as quasiparticles has grown quickly and become more and more exotic. Here are a few of the most curious and potentially useful examples.

Graphic of swirling vortex-like patterns called skyrmions.
condensed matter physics

A New Twist Reveals Superconductivity’s Secrets

March 16, 2021

An unexpected superconductor was beginning to look like a fluke, but a new theory and a second discovery have revealed that emergent quasiparticles may be behind the effect.

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quantum gravity

Quantum Mischief Rewrites the Laws of Cause and Effect

March 11, 2021

Spurred on by quantum experiments that scramble the ordering of causes and their effects, some physicists are figuring out how to abandon causality altogether.

An abstract black ball on a blue background.
Abstractions blog

In Violation of Einstein, Black Holes Might Have ‘Hair’

February 11, 2021

A new study shows that extreme black holes could break the famous “no-hair” theorem, and in a way that we could detect.

Q&A

A Prodigy Who Cracked Open the Cosmos

January 12, 2021

Frank Wilczek has been at the forefront of theoretical physics for the past 50 years. He talks about winning the Nobel Prize for work he did as a student, his solution to the dark matter problem, and the God of a scientist.

A stylized atom surrounded by concentric shells of increasingly complex organisms.
quantum physics

A New Theorem Maps Out the Limits of Quantum Physics

December 3, 2020

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.

Illustration of a particle
Hidden Structure

What Is a Particle?

November 12, 2020

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.

Cora Dvorkin in front of a starry backdrop.
Hidden Structure

The Cosmologist Who Dreams in the Universe’s Dark Threads

November 5, 2020

Cora Dvorkin discovered new possibilities for what dark matter could be. Now she’s devising unorthodox ways to identify it.