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theoretical physics

quantum physics

Quantum Weirdness Now a Matter of Time

Bizarre quantum bonds connect distinct moments in time, suggesting that quantum links — not space-time — constitute the fundamental structure of the universe.


String Theory Meets Loop Quantum Gravity

Two leading candidates for a “theory of everything,” long thought to be incompatible, may be two sides of the same coin.

Quantized Columns

Time’s (Almost) Reversible Arrow

The irreversibility of time may be a clue as to what makes up the universe’s dark matter.


A Fight for the Soul of Science

If a theory can’t be tested, is it still science?


Visions of Future Physics

Nima Arkani-Hamed is championing a campaign to build the world’s largest particle collider, even as he pursues a new vision of the laws of nature.


Theories of Everything, Mapped

Explore the deepest mysteries at the frontier of fundamental physics, and the most promising ideas put forth to solve them.

condensed matter physics

Paradoxical Crystal Baffles Physicists

At super-low temperatures, a crystal called samarium hexaboride behaves in an unexplained, imagination-stretching way.


The Fuzzball Fix for a Black Hole Paradox

By replacing black holes with fuzzballs — dense, star-like objects from string theory — researchers think they can avoid some knotty paradoxes at the edge of physics.


A Private View of Quantum Reality

Quantum theorist Christopher Fuchs explains how to solve the paradoxes of quantum mechanics. His price: physics gets personal.