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# theoretical physics

## Latest Articles

### Quantum Complexity Tamed by Machine Learning

If only scientists understood exactly how electrons act in molecules, they’d be able to predict the behavior of everything from experimental drugs to high-temperature superconductors. Following decades of physics-based insights, artificial intelligence systems are taking the next leap.

### In a Numerical Coincidence, Some See Evidence for String Theory

In a quest to map out a quantum theory of gravity, researchers have used logical rules to calculate how much Einstein’s theory must change. The result matches string theory perfectly.

### Symmetries Reveal Clues About the Holographic Universe

Physicists have been busy exploring how our universe might emerge like a hologram out of a two-dimensional sheet. New clues have come from the symmetries found on an infinitely distant “celestial sphere.”

### Laws of Logic Lead to New Restrictions on the Big Bang

Physicists are translating commonsense principles into strict mathematical constraints on how our universe must have behaved at the beginning of time.

### Is the Great Neutrino Puzzle Pointing to Multiple Missing Particles?

Years of conflicting neutrino measurements have led physicists to propose a “dark sector” of invisible particles — one that could simultaneously explain dark matter, the puzzling expansion of the universe, and other mysteries.

### The New Thermodynamic Understanding of Clocks

Investigations of the simplest possible clocks have revealed their fundamental limitations — as well as insights into the nature of time itself.

### This Physicist Discovered an Escape From Hawking’s Black Hole Paradox

The five-decade-old paradox — long thought key to linking quantum theory with Einstein’s theory of gravity — is falling to a new generation of thinkers. Netta Engelhardt is leading the way.

### The ‘Weirdest’ Matter, Made of Partial Particles, Defies Description

Theorists are in a frenzy over “fractons,” bizarre, but potentially useful, hypothetical particles that can only move in combination with one another.

### How Bell’s Theorem Proved ‘Spooky Action at a Distance’ Is Real

The root of today’s quantum revolution was John Stewart Bell’s 1964 theorem showing that quantum mechanics really permits instantaneous connections between far-apart locations.