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theoretical physics

Black holes of various sizes
black holes

Physicists Argue That Black Holes From the Big Bang Could Be the Dark Matter

September 23, 2020

It was an old idea of Stephen Hawking’s: Unseen “primordial” black holes might be the hidden dark matter. A new series of studies has shown how the theory can work.

water molecules, droplets and a wave
Abstractions blog

How Mathematical ‘Hocus-Pocus’ Saved Particle Physics

September 17, 2020

Renormalization has become perhaps the single most important advance in theoretical physics in 50 years.

An animation of a particle collision
Abstractions blog

The Mathematical Structure of Particle Collisions Comes Into View

August 20, 2020

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.

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.

The cyclic universe.
Abstractions blog

Big Bounce Simulations Challenge the Big Bang

August 4, 2020

Detailed computer simulations have found that a cosmic contraction can generate features of the universe that we observe today.

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.

Animated illustration of a hand emerging from a black hole, while drawing the black hole by connecting dots flashing 0 and 1.
Quantized Columns

Spotting Quantum Black Holes in the Lab

July 15, 2020

Can we test speculations about how quantum physics affects black holes and the Big Bang?

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.