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quantum gravity

Craig Callender holding a paddleboard at the beach.
Q&A

Are We All Wrong About Black Holes?

September 5, 2019

Since the 1970s, physicists have described black holes using borrowed versions of the laws of thermodynamics. But are black holes really thermodynamic systems? Craig Callender worries that the analogy has been stretched too far.

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.

Abstractions blog

Philosophers Debate New ‘Sonic Black Hole’ Discovery

June 25, 2019

Opinions differ about what recent measurements of a sound-trapping fluid reveal about light-trapping black holes.

Art for "How Our Universe Could Emerge as a Hologram"
Abstractions blog

How Our Universe Could Emerge as a Hologram

February 21, 2019

Physicists have devised a holographic model of “de Sitter space,” the term for a universe like ours, that could give us new clues about the origin of space and time.

Quantized Columns

The Double Life of Black Holes

January 29, 2019

Perfect black holes are versatile mathematical tools. Just don’t mistake them for the real thing.

Art for "How Space and Time Could Be a Quantum Error-Correcting Code"
space-time

How Space and Time Could Be a Quantum Error-Correcting Code

January 3, 2019

The same codes needed to thwart errors in quantum computers may also give the fabric of space-time its intrinsic robustness.

Art for "How Holography Could Help Solve Quantum Gravity"
In Theory

How Holography Could Help Solve Quantum Gravity

November 14, 2018

In the latest campaign to reconcile Einstein’s theory of gravity with quantum mechanics, many physicists are studying how a higher dimensional space that includes gravity arises like a hologram from a lower dimensional particle theory.

Art for "Black Hole Firewalls Could Be Too Tepid to Burn"
Abstractions blog

Black Hole Firewalls Could Be Too Tepid to Burn

August 22, 2018

String theorists elide a paradox about black holes by extinguishing the walls of fire feared to surround them.

Art for "Dark Energy May Be Incompatible With String Theory"
theoretical physics

Dark Energy May Be Incompatible With String Theory

August 9, 2018

A controversial new paper argues that universes with dark energy profiles like ours do not exist in the “landscape” of universes allowed by string theory.