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Physics

astrobiology

Scientists Debate Signatures of Alien Life

Searching for signs of life on faraway planets, astrobiologists must decide which telltale biosignature gases to target.

Q&A

Taming Superconductors With String Theory

The physicist Subir Sachdev borrows tools from string theory to understand the puzzling behavior of high-temperature superconductors.

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.

Physics

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.

Physics

A Fight for the Soul of Science

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

complex systems

Nature’s Critical Warning System

Scientists are homing in on a warning signal that arises in complex systems like ecological food webs, the brain and the Earth’s climate. Could it help prevent future catastrophes?

Q&A

Searching the Sky for the Wobbles of Gravity

The physicist Gabriela González is on the cusp of finding the first direct evidence of gravitational waves — soundlike wobbles in space-time produced by black holes and their kin.

Physics

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.