Quantum physics

Richard Feynman’s path integral is both a powerful prediction machine and a philosophy about how the world is. But physicists are still struggling to figure out how to use it, and what it means.

Two teams have made photons act as if time were simultaneously flowing in two directions. The experiments demonstrate a way to potentially boost the performance of quantum devices.

Computer scientists this year learned how to transmit perfect secrets, why transformers seem so good at everything, and how to improve on decades-old algorithms (with a little help from AI).

The unprecedented experiment explores the possibility that space-time somehow emerges from quantum information.

A team of physicists has entangled three photons over a considerable distance, which could lead to more powerful quantum cryptography.

Physical-collapse theories have long offered a natural solution to the central mystery of the quantum world. But a series of increasingly precise experiments are making them untenable.

The positively charged particle at the heart of the atom is an object of unspeakable complexity, one that changes its appearance depending on how it is probed.

Alain Aspect, John Clauser and Anton Zeilinger have won the 2022 Nobel Prize in Physics for groundbreaking experiments with entangled particles.

The past and the future are tightly linked in conventional quantum mechanics. Perhaps too tightly. A tweak to the theory could let quantum possibilities increase as space expands.