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space-time

Art for "How Holography Could Help Solve Quantum Gravity"
multimedia

How Holography Could Help Solve Quantum Gravity

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.

Photo of Cohl Furey
fundamental physics

The Peculiar Math That Could Underlie the Laws of Nature

New findings are fueling an old suspicion that fundamental particles and forces spring from strange eight-part numbers called “octonions.”

Illustration of a black hole with a Cauchy horizon
general relativity

Mathematicians Disprove Conjecture Made to Save Black Holes

Mathematicians have disproved the strong cosmic censorship conjecture. Their work answers one of the most important questions in the study of general relativity and changes the way we think about space-time.

An illustration of gravity as particles
gravity

Physicists Find a Way to See the ‘Grin’ of Quantum Gravity

A recently proposed experiment would confirm that gravity is a quantum force.

Edward Witten in his office at the Institute for Advanced Study in Princeton, New Jersey.
Q&A

A Physicist’s Physicist Ponders the Nature of Reality

Edward Witten reflects on the meaning of dualities in physics and math, emergent space-time, and the pursuit of a complete description of nature.

A wormhole split in two with swirls of blue on one side and swirls of pink on the other with a ringed planet in the background.
theoretical physics

Newfound Wormhole Allows Information to Escape Black Holes

Physicists theorize that a new “traversable” kind of wormhole could resolve a baffling paradox and rescue information that falls into black holes.

Warped time. Olena Shmahalo/Quanta Magazine
Abstractions blog

Quantum Gravity’s Time Problem

The effort to unify quantum mechanics and general relativity means reconciling totally different notions of time.

string theory

The Strange Second Life of String Theory

String theory has so far failed to live up to its promise as a way to unite gravity and quantum mechanics. At the same time, it has blossomed into one of the most useful sets of tools in science.

astrophysics

Colliding Black Holes Tell New Story of Stars

Just months after their discovery, gravitational waves coming from the mergers of black holes are shaking up astrophysics.