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theoretical physics

Boucing droplet
quantum physics

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

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.

Q&A

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
cosmology

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.

Gravitons
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.

cosmology

Lopsided Map Offers Clues to Big Bang

Theoretical cosmologists are piecing together a cosmic origin story from a surprising anomaly in the recently released Planck satellite image.

theoretical physics

Is Nature Unnatural?

Decades of confounding experiments have physicists considering a startling possibility: The universe might not make sense.