Quantum gravity

Physics

Spin glass

Replica

Mathematics

Euclidean geometry

Epistemology

Instanton

Visual arts

Philosophy

Political science

Geometry

Replica trick

Wormhole

Theoretical physics

Simple (philosophy)

Quantum mechanics

Unitary state

Classical mechanics

Quantum

Physical Review Letters

Naively, resolving the black hole information paradox requires microscopic details about quantum gravity. Recent work suggests that, instead, a unitary Page curve can be recovered by adding disorder-averaged replica instantons to the path integral, though their origin is unclear. In this Letter, we show how replica instantons and disorder averaging emerge naturally in an effective theory built from typical microscopic states. We relate replica instantons to a moment expansion of simple operators, and find a microcanonical description in terms of wormholes and Euclidean black holes.

Eigenstate Thermalization and Disorder Averaging in Gravity