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quantum gravity

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.

Physics

A Fight for the Soul of Science

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

Multimedia

Theories of Everything, Mapped

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

Physics

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.

The Quantum Fabric of Space-Time

Interactive: What Is Space?

Imagine the fabric of space-time peeled back layer by layer.

The Quantum Fabric of Space-Time

How Quantum Pairs Stitch Space-Time

New tools may reveal how quantum information builds the structure of space.

The Quantum Fabric of Space-Time

Wormholes Untangle a Black Hole Paradox

A bold new idea aims to link two famously discordant descriptions of nature. In doing so, it may also reveal how space-time owes its existence to the spooky connections of quantum information.

theoretical physics

In Fake Universes, Evidence for String Theory

If string theorists can show that their framework is the only consistent theory of quantum gravity, does that make it true even without tangible evidence?

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.