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A Debate Over the Physics of Time

According to our best theories of physics, the universe is a fixed block where time only appears to pass.

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.

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.

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.


Perpetual Motion Test Could Amend Theory of Time

A radical theory predicting the existence of “time crystals” — perpetual motion objects that break the symmetry of time — is being put to the test.