Theoretical physics

Last fall, a team of physicists announced that they had teleported a qubit through a holographic wormhole in a quantum computer. Now another group suggests that’s not quite what happened.

Using “refreshingly old” tools, mathematicians resolved a 50-year-old conjecture about how to categorize important functions called modular forms, with consequences for number theory and theoretical physics.

New calculations suggest that the event horizons around black holes will ‘decohere’ quantum possibilities — even those that are far away.

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.

Maintenance of the software that’s used for the hardest physics calculations rests almost entirely with a retiree. The situation reveals the problematic incentive structure of academia.

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

Two physicists have calculated that the universe has a higher entropy — and is therefore more likely — than alternative possible universes.

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.