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theoretical physics

520px illustration for the bounce model theory
cosmology

How the Universe Got Its Bounce Back

Cosmologists have shown that it’s theoretically possible for a contracting universe to bounce and expand. The new work resuscitates an old idea that directly challenges the Big Bang theory of cosmic origins.

520 Illustration for Quantum Gravity
Quantized Columns

Why an Old Theory of Everything Is Gaining New Life

For decades, physicists have struggled to create a quantum theory of gravity. Now an approach that dates to the 1970s is attracting newfound attention.

520px illustration of classification of phases
condensed matter physics

Physicists Aim to Classify All Possible Phases of Matter

A complete classification could lead to a wealth of new materials and technologies. But some exotic phases continue to resist understanding.

M theory and its six components
Abstractions blog

Why Is M-Theory the Leading Candidate for Theory of Everything?

The mother of all string theories passes a litmus test that, so far, no other candidate theory of quantum gravity has been able to match.

Edward Witten in his office at the Institute for Advanced Study in Princeton, New Jersey.
Q&A

A Physicist’s Physicist Ponders the Nature of Reality

Edward Witten reflects on the meaning of dualities in physics and math, emergent space-time, and the pursuit of a complete description of nature.

A wormhole split in two with swirls of blue on one side and swirls of pink on the other with a ringed planet in the background.
theoretical physics

Newfound Wormhole Allows Information to Escape Black Holes

Physicists theorize that a new “traversable” kind of wormhole could resolve a baffling paradox and rescue information that falls into black holes.

Particle trails
particle physics

How the Hidden Higgs Could Reveal Our Universe’s Dark Sector

The universe has not cooperated with physicists’ hopes. In desperation, many are looking for new ways to search for surprises at the Large Hadron Collider.

Emergent reductionism flower
Quantized Columns

To Solve the Biggest Mystery in Physics, Join Two Kinds of Law

Reductionism breaks the world into elementary building blocks. Emergence finds the simple laws that arise out of complexity. These two complementary ways of viewing the universe come together in modern theories of quantum gravity.

Quantum reconstruction
quantum mechanics

Quantum Theory Rebuilt From Simple Physical Principles

Physicists are trying to rewrite the axioms of quantum theory from scratch in an effort to understand what it all means. The problem? They’ve been almost too successful.