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quantum gravity

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.

Illustration of a black hole
Hidden Structure

The Most Famous Paradox in Physics Nears Its End

October 29, 2020

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

Claudia de Rham portrait
Q&A

The Physicist Who Slayed Gravity’s Ghosts

August 18, 2020

Claudia de Rham showed how theories of “massive gravity” could potentially get rid of the need for dark energy.

An apple being jostled by gravitons
gravitational waves

How the Bits of Quantum Gravity Can Buzz

July 23, 2020

New calculations show how hypothetical particles called gravitons would give rise to a special kind of noise.

A black hole shooting thunderbolts.
quantum gravity

Black Hole Paradoxes Reveal a Fundamental Link Between Energy and Order

May 28, 2020

By chewing on the problems posed by “extremal” black holes, physicists have exposed a surprising and universal connection between energy and entropy.

theoretical physics

Does Time Really Flow? New Clues Come From a Century-Old Approach to Math.

April 7, 2020

The laws of physics imply that the passage of time is an illusion. To avoid this conclusion, we might have to rethink the reality of infinitely precise numbers.

A domino, a two of clubs, and a clock face.
Abstractions blog

Why the Laws of Physics Are Inevitable

December 9, 2019

By considering simple symmetries, physicists working on the “bootstrap” can rediscover the basic form of the known forces that shape the universe.

Animation of a black hole rotating.
Abstractions blog

Black Hole Singularities Are as Inescapable as Expected

December 2, 2019

For the first time, physicists have calculated exactly what kind of singularity lies at the center of a realistic black hole.

symmetry

The Simple Idea Behind Einstein’s Greatest Discoveries

June 26, 2019

Lurking behind Einstein’s theory of gravity and our modern understanding of particle physics is the deceptively simple idea of symmetry. But physicists are beginning to question whether focusing on symmetry is still as productive as it once was.