Decoherence of Cosmological Perturbations from Boundary Terms and the Non-Classicality of Gravity

Abstract

We note that the decoherence of inflationary curvature perturbation $\zeta$ is dominated by a boundary term of the gravity action. Although this boundary term cannot affect cosmological correlators $⟨{\zeta }^n⟩$, it induces much faster decoherence for $\zeta$ than that of previous calculations. The gravitational origin of inflationary decoherence sheds light on the quantum (or non-classical) nature of gravity. By comparing with a Schrödinger-Newton toy model of classical gravity, we show that gravity theories of classical or quantum origins can be distinguished by comparing their different impacts on decoherence rate of $\zeta$. Our calculation also indicates that density fluctuation $\delta \rho$ better preserves quantum information than $\zeta$ for the purpose of constructing cosmological Bell-like experiments.

arXiv commentv3: 34 pages, 3 figures; typos corrected, references and figure added. Revised the part of UV and IR divergences. Match the JHEP version

References in corpus (41)

• Quantum entanglement
• Non-Gaussian features of primordial fluctuations in single field inflationary models
• The Dynamics of General Relativity
• A Spin Entanglement Witness for Quantum Gravity
• Gravitationally-induced entanglement between two massive particles is sufficient evidence of quantum effects in gravity
• Semiclassicality and Decoherence of Cosmological Perturbations
• Inflation and squeezed quantum states
• Quantum-to-classical transition for fluctuations in the early Universe
• Quantum Fluctuations, Decoherence of the Mean Field, and Structure Formation in the Early Universe
• Locality & Entanglement in Table-Top Testing of the Quantum Nature of Linearized Gravity
• Quantum-to-classical Transition of Cosmological Perturbations for Non-vacuum Initial States
• Pointer states for primordial fluctuations in inflationary cosmology
• Decoherence during Inflation: the generation of classical inhomogeneities
• Quantum Discord of Cosmic Inflation: Can we Show that CMB Anisotropies are of Quantum-Mechanical Origin?
• Inflation, Cosmic Perturbations and Non-Gaussianities
• Cosmological Inflation and the Quantum Measurement Problem
• On the Decoherence of Primordial Fluctuations During Inflation
• Mechanism for the quantum natured gravitons to entangle masses
• Entropy of a Classical Stochastic Field and Cosmological Perturbation
• An effective field theory during inflation: reduced density matrix and its quantum master equation
• The Entropy of the Gravitational Field
• Non-Gaussianity as a signature of a quantum theory of gravity
• Large slow-roll corrections to the bispectrum of noncanonical inflation
• Quantum Decoherence During Inflation from Gravitational Nonlinearities
• Signals of a Quantum Universe
• Entanglement Entropy of Cosmological Perturbations
• Obstructions to Bell CMB Experiments
• On the time evolution of cosmological correlators
• A note on the role of the boundary terms for the non-Gaussianity in general k-inflation
• Bell violation in the Sky
• Observational constraints on quantum decoherence during inflation
• Inflation and de Sitter Holography
• A no-go theorem on the nature of the gravitational field beyond quantum theory
• Quantum discord in de Sitter space
• Boundary terms of the Einstein-Hilbert action
• The Quantum Information of Cosmological Correlations
• Uniqueness of the gauge invariant action for cosmological perturbations
• Gauge invariance and non-Gaussianity in Inflation
• Cosmic Decoherence: Massive Fields
• Primordial Non-Gaussianity in Supersolid Inflation
• Entropy production in inflation from spectator loops

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