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general relativity

An illustration of an airplane with its contrails coming out in front of it.
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.

Abstractions blog

Physics Nobel Awarded for Black Hole Breakthroughs

October 6, 2020

Roger Penrose, Reinhard Genzel and Andrea Ghez were awarded the Nobel Prize in Physics for their studies of black holes.

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.

A falling apple.
Abstractions blog

Why Gravity Is Not Like the Other Forces

June 15, 2020

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

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.

Animation of black hole formation.
mathematical physics

New Math Proves That a Special Kind of Space-Time Is Unstable

May 11, 2020

Einstein’s equations describe three canonical configurations of space-time. Now one of these three — important in the study of quantum gravity — has been shown to be inherently unstable.

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.

Multimedia

The Map of Mathematics

February 13, 2020

Explore our surprisingly simple, absurdly ambitious and necessarily incomplete guide to the boundless mathematical universe.