Quantum Spacetime, Quantum Gravity and Gravitized Quantum Theory

TL;DR

This paper explores how quantum gravity's background independence and non-commutative spacetime structures influence the probabilistic and contextual nature of quantum theory, with implications for string theory and particle physics.

Contribution

It proposes that quantum gravity's non-commutative spacetime explains quantum theory's probabilistic and contextual features, extending to higher-order interference phenomena.

Findings

Quantum gravity induces a non-commutative dual to classical spacetime.

Intrinsic higher-order interference arises in massive quantum probes.

Implications for string theory, vacuum energy, and elementary particle masses.

Abstract

General relativity is a background-independent theory of a dynamical classical spacetime geometry. Quantum theory is formulated in a classical spacetime, as an intrinsically probabilistic, contextual theory of non-classical, interfering probabilities, with a fixed Born rule for computing those probabilities. We argue that the quantum nature of spacetime, which includes a non-commutative dual companion to the (observed) classical spacetime, is the reason behind an intrinsically probabilistic and contextual nature of quantum theory, with the fixed Born rule. In quantum gravity, we claim, quantum theory is gravitized into a background-independent structure with dynamical and contextual quantum probabilities. This proposal implies intrinsic triple and higher-order interference in the context of massive quantum probes, which sheds light on string theory and the observed vacuum energy as well as the masses of elementary particles.