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general relativity

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.

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.