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theoretical physics

theoretical physics

At Multiverse Impasse, a New Theory of Scale

Physicists have begun to explore the idea that mass and length may not be fundamental properties of nature. The hypothesis could help to avoid the conclusion that our world is just a weird bubble in an endlessly foaming multiverse.

Katherine Freese

In Search of Dark Stars

Katherine Freese, a physicist who will soon lead the Nordic Institute for Theoretical Physics, reflects on the hunt for dark matter and how dark matter heating may have produced the first stars.

Boucing droplet
quantum mechanics

Fluid Tests Hint at Concrete Quantum Reality

Surprising oil drop experiments suggest that the quantum world may not be as strange as advertised.

The arrow of time.

Time’s Arrow Traced to Quantum Source

A new theory explains the seemingly irreversible arrow of time while yielding insights into entropy, quantum computers, black holes, and the past-future divide.


A ‘Rebel’ Without a Ph.D.

A conversation with the mathematical physicist Freeman Dyson on quantum electrodynamics, climate change and his latest pet project.

Bicep2 B-modes

Possible Echo of Big Bang Detected

Scientists report the possible discovery of primordial gravitational waves, ripples in space-time that carry a record of how the universe began.

theoretical physics

Betting on the Future of Quantum Gravity

New calculations suggest physicists may someday discover a fundamental theory of gravity, but it could require a radical new perspective on the universe.

quantum gravity

Physicists Eye Quantum-Gravity Interface

Physicists have devised experiments that can probe the interface between quantum mechanics and general relativity.

Illustration of an amplituhedron.
theoretical physics

A Jewel at the Heart of Quantum Physics

Physicists have discovered a jewel-shaped geometric object that challenges the notion that space and time are fundamental constituents of nature.