Inference of gravitational field superposition from quantum measurements

Abstract

Experiments are beginning to probe the interaction of quantum particles with gravitational fields beyond the uniform-field regime. In non-relativistic quantum mechanics, the gravitational field in such experiments can be written as a superposition state. We empirically demonstrate that alternative theories of gravity can avoid gravitational superposition states only by decoupling the gravitational field energy from the quantum particle's time evolution. Furthermore, such theories must specify a preferred quantum reference frame in which the equations of motion are valid. To the extent that these properties are theoretically implausible, recent experiments provide indirect evidence that gravity has quantum features. Proposed experiments with superposed gravitational sources would provide even stronger evidence that gravity is nonclassical.

15 pages, 7 figures. Closely matches the published version

References in corpus (16)

• The Confrontation between General Relativity and Experiment
• A Spin Entanglement Witness for Quantum Gravity
• Reference frames, superselection rules, and quantum information
• Gravitationally-induced entanglement between two massive particles is sufficient evidence of quantum effects in gravity
• The resource theory of quantum reference frames: manipulations and monotones
• Gravitationally Mediated Entanglement: Newtonian Field vs. Gravitons
• Mechanism for the quantum natured gravitons to entangle masses
• Problems with the Newton-Schrödinger Equations
• Decoherence effects in non-classicality tests of gravity
• On two recent proposals for witnessing nonclassical gravity
• Dynamics of a Quantum Reference Frame
• Catapulting towards massive and large spatial quantum superposition
• Gravity entanglement, quantum reference systems, degrees of freedom
• Entanglement Witness for the Weak Equivalence Principle
• Quantum reference frames for an indefinite metric
• Entanglement-asymmetry correspondence for internal quantum reference frames

Cited by in corpus (13)

• Massive quantum systems as interfaces of quantum mechanics and gravity
• Quantum Cloud Computing: Trends and Challenges
• Optimal Floquet Engineering for Large Scale Atom Interferometers
• Stabilizer entropy of quantum tetrahedra
• Imprints of screened dark energy on nonlocal quantum correlations
• Quantum generalisation of Einstein's Equivalence Principle can be verified with entangled clocks as quantum reference frames
• Quantum Sensing from Gravity as Universal Dephasing Channel for Qubits
• Accelerated detector in a superposed spacetime
• How to Minimize the Decoherence Caused by Black Holes
• Newton's laws of motion generating gravity-mediated entanglement
• Doubly Quantum Mechanics
• Driven-Dissipative Dynamics of Ultracold Atoms Trapped in an Array of Harmonic Potentials
• Quantum Galilei group as quantum reference frame transformations