Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:2012.10626 · Physical Review Research

Decoherence-free entropic gravity: Model and experimental tests

Alex J. Schimmoller, Gerard McCaul, Hartmut Abele, Denys I. Bondar

Published Jul 19, 2021• 21 citations
arXivHTMLPDF

Abstract

Erik Verlinde's theory of entropic gravity [E. Verlinde, J. High Energy Phys. 04 (2011) 029], postulating that gravity is not a fundamental force but rather emerges thermodynamically, has garnered much attention as a possible resolution to the quantum gravity problem. Some have ruled this theory out on grounds that entropic forces are by nature noisy and entropic gravity would therefore display far more decoherence than is observed in ultracold neutron experiments. We address this criticism by modeling linear gravity acting on small objects as an open quantum system. In the strong coupling limit, when the model's unitless free parameter $\ensuremath{\sigma}$ goes to infinity, the entropic master equation recovers conservative gravity. We show that the proposed master equation is fully compatible with the $q$Bounce experiment for ultracold neutrons as long as $\ensuremath{\sigma}\ensuremath{\gtrsim}250$ at $90%$ confidence. Furthermore, the entropic master equation predicts energy increase and decoherence on long time scales and for large masses, phenomena that tabletop experiments could test. In addition, comparing entropic gravity's energy increase to that of the Di\'osi-Penrose model for gravity-induced decoherence indicates that the two theories are incompatible. These findings support the theory of entropic gravity, motivating future experimental and theoretical research.

DOI
10.1103/physrevresearch.3.033065

Related papers

A testable prediction from entropic gravity

Mehmet Süzen

I have shown conceptually that quantum state has a direct relationship to gravitational constant due to entropic force posed by Verlinde's argument and part of the Newton-Schrödinger equation (N-S) in the context of gravity induced collapse of the wavefunction via Diósi-Penrose proposal. This direct relationship can be used to measure gravitational constant using state-of-the-art mater-wave interferometry to test the entropic gravity argument.

arXiv:1612.00288•Nov 27, 2016•0 citations

Time–Decoherence Gravity (TDG): A Unified Framework

Duchesne, Jonathan

Contact Jonathan.duchesne@hotmail.com 418-953-0596 This thesis presents Time–Decoherence Gravity (TDG), a unified theoretical framework in which spacetime geometry, gravitation, and the physical flow of time arise from fundamental quantum decoherence. Rather than treating decoherence as an environmental or effective process, TDG builds on a covariant extension of the Gorini–Kossakowski–Sudarshan–Lindblad (GKSL) equation, where four directional Lindblad operators encode intrinsic, irreversible information loss. These operators define a “decoherence tensor,” which acts both as a memory of quantum irreversibility and as the generator of emergent spacetime geometry through a nonlinear constitutive relation. The theory provides a coherent gravitational collapse mechanism based on the incompatibility of decoherence patterns across quantum branches. This leads to an intrinsic “decoherence energy,” whose magnitude determines the collapse timescale, extending and generalizing the well-known Penrose–Diósi models. TDG predicts a smooth transition from persistent microscopic coherence to rapid macroscopic collapse. At cosmological scales, a homogeneous decoherence tensor naturally generates modified Friedmann dynamics, early-universe stiff-fluid behavior, and late-time acceleration without requiring a fine-tuned cosmological constant. Black-hole entropy emerges as a saturation of decoherence memory at the horizon, while Hawking radiation appears as the dissipative relaxation of this saturation. The theory also predicts short-range deviations from Newtonian gravity and a universal spectrum of fundamental gravitational noise. Finally, TDG offers several experimentally testable signatures involving optical clocks, mesoscopic interferometry, short-range force measurements, and correlated phase noise in global timing networks. The framework is internally consistent, falsifiable, and provides a novel and unified approach to the relationship between quantum mechanics, gravity, and the arrow of time.

•Nov 20, 2025•0 citations

A master equation for gravitational decoherence: probing the textures of spacetime

Charis Anastopoulos, B. L. Hu

We give a first principles derivation of a master equation for the evolution of a quantum matter field in a linearly perturbed Minkowski spacetime, based solely on quantum field theory and general relativity. We make no additional assumptions nor introduce extra ingredients, as is often done in alternative quantum theories. When the quantum matter field is projected to a one-particle state, the master equation for a non-relativistic quantum particle in a weak gravitational field predicts decoherence in the energy basis , in contrast to most existing theories of gravitational decoherence. We point out the gauge nature of time and space reparameterizations in matter–gravity couplings, and warn that 'intrinsic' decoherence or alternative quantum theories invoking stochastic dynamics arising from temporal or spatial fluctuations violate this fundamental symmetry of classical general relativity. Interestingly we find that the decoherence rate depends on extra parameters other than the Planck scale, an important feature of gravitational decoherence. This is similar to the dependence of the decoherence rate of a quantum Brownian particle to the temperature and spectral density of the environment it interacts with. The corresponding features when gravity acts as an environment in decohering quantum objects are what we call the ' textures' of spacetime . We point out the marked difference between the case when gravity is represented as a background spacetime versus the case when gravity acts like a thermodynamic bath to quantum particles. This points to the possibility of using gravitational decoherence measurements to discern whether gravity is intrinsically elemental or emergent.

arXiv:1305.5231•Classical and Quantum Gravity•Jul 18, 2013•155 citations

Gravitationally induced decoherence vs space-time diffusion: testing the quantum nature of gravity

Jonathan Oppenheim, Carlo Sparaciari, Barbara Šoda +1 more

We consider two interacting systems when one is treated classically while the other system remains quantum. Consistent dynamics of this coupling has been shown to exist, and explored in the context of treating space-time classically. Here, we prove that any such hybrid dynamics necessarily results in decoherence of the quantum system, and a breakdown in predictability in the classical phase space. We further prove that a trade-off between the rate of this decoherence and the degree of diffusion induced in the classical system is a general feature of all classical quantum dynamics; long coherence times require strong diffusion in phase-space relative to the strength of the coupling. Applying the trade-off relation to gravity, we find a relationship between the strength of gravitationally-induced decoherence versus diffusion of the metric and its conjugate momenta. This provides an experimental signature of theories in which gravity is fundamentally classical. Bounds on decoherence rates arising from current interferometry experiments, combined with precision measurements of mass, place significant restrictions on theories where Einstein's classical theory of gravity interacts with quantum matter. We find that part of the parameter space of such theories are already squeezed out, and provide figures of merit which can be used in future mass measurements and interference experiments.

Nature Communications•Dec 4, 2023•58 citations

Gravitationally induced decoherence vs space-time diffusion: testing the quantum nature of gravity

Jonathan Oppenheim, Carlo Sparaciari, Barbara Šoda +1 more

We consider two interacting systems when one is treated classically while the other system remains quantum. Consistent dynamics of this coupling has been shown to exist, and explored in the context of treating space-time classically. Here, we prove that such hybrid dynamics necessarily results in decoherence of the quantum system, and a breakdown in predictability in the classical phase space. We further prove that a trade-off between the rate of this decoherence and the degree of diffusion induced in the classical system is a general feature of all classical quantum dynamics; long coherence times require strong diffusion in phase-space relative to the strength of the coupling. Applying the trade-off relation to gravity, we find a relationship between the strength of gravitationally-induced decoherence versus diffusion of the metric and its conjugate momenta. This provides an experimental signature of theories in which gravity is fundamentally classical. Bounds on decoherence rates arising from current interferometry experiments, combined with precision measurements of mass, place significant restrictions on theories where Einstein's classical theory of gravity interacts with quantum matter. We find that part of the parameter space of such theories are already squeezed out, and provide figures of merit which can be used in future mass measurements and interference experiments.

arXiv:2203.01982•Mar 3, 2022•5 citations

Quantum gravitational decoherence

Luciano Petruzziello, Fabrizio Illuminati

We introduce and investigate a decoherence mechanism due to quantum gravity effects. By assuming the existence of a fluctuating minimal space length scale, we derive a master equation in Lindblad form induced by the minimal-length-deformed uncertainty principle and we analyze its implications for the decoherence time and the state entropy variation. Further, we show how our model predicts a localization in energy and decoherence timescales consistent with the currently available observational evidence. Finally, we discuss schemes for the experimental verification of our model based on cavity optomechanics setups with ultracold massive molecular oscillators.

•Nov 2, 2020•1 citation
Erik Verlinde's theory of entropic gravity [E. Verlinde, J. High Energy Phys. 04 (2011) 029], postulating that gravity is not a fundamental force but rather emerges thermodynamically, has garnered much attention as a possible resolution to the quantum gravity problem. Some have ruled this theory out on grounds that entropic forces are by nature noisy and entropic gravity would therefore display far more decoherence than is observed in ultracold neutron experiments. We address this criticism by modeling linear gravity acting on small objects as an open quantum system. In the strong coupling limit, when the model's unitless free parameter \ensuremathσ\ensuremath{\sigma}\ensuremathσ goes to infinity, the entropic master equation recovers conservative gravity. We show that the proposed master equation is fully compatible with the qqqBounce experiment for ultracold neutrons as long as \ensuremathσ\ensuremath≳250\ensuremath{\sigma}\ensuremath{\gtrsim}250\ensuremathσ\ensuremath≳250 at 9090%90 confidence. Furthermore, the entropic master equation predicts energy increase and decoherence on long time scales and for large masses, phenomena that tabletop experiments could test. In addition, comparing entropic gravity's energy increase to that of the Di'osi-Penrose model for gravity-induced decoherence indicates that the two theories are incompatible. These findings support the theory of entropic gravity, motivating future experimental and theoretical research.
Contact Jonathan.duchesne@hotmail.com 418-953-0596 This thesis presents Time–Decoherence Gravity (TDG), a unified theoretical framework in which spacetime geometry, gravitation, and the physical flow of time arise from fundamental quantum decoherence. Rather than treating decoherence as an environmental or effective process, TDG builds on a covariant extension of the Gorini–Kossakowski–Sudarshan–Lindblad (GKSL) equation, where four directional Lindblad operators encode intrinsic, irreversible information loss. These operators define a “decoherence tensor,” which acts both as a memory of quantum irreversibility and as the generator of emergent spacetime geometry through a nonlinear constitutive relation. The theory provides a coherent gravitational collapse mechanism based on the incompatibility of decoherence patterns across quantum branches. This leads to an intrinsic “decoherence energy,” whose magnitude determines the collapse timescale, extending and generalizing the well-known Penrose–Diósi models. TDG predicts a smooth transition from persistent microscopic coherence to rapid macroscopic collapse. At cosmological scales, a homogeneous decoherence tensor naturally generates modified Friedmann dynamics, early-universe stiff-fluid behavior, and late-time acceleration without requiring a fine-tuned cosmological constant. Black-hole entropy emerges as a saturation of decoherence memory at the horizon, while Hawking radiation appears as the dissipative relaxation of this saturation. The theory also predicts short-range deviations from Newtonian gravity and a universal spectrum of fundamental gravitational noise. Finally, TDG offers several experimentally testable signatures involving optical clocks, mesoscopic interferometry, short-range force measurements, and correlated phase noise in global timing networks. The framework is internally consistent, falsifiable, and provides a novel and unified approach to the relationship between quantum mechanics, gravity, and the arrow of time.
We give a first principles derivation of a master equation for the evolution of a quantum matter field in a linearly perturbed Minkowski spacetime, based solely on quantum field theory and general relativity. We make no additional assumptions nor introduce extra ingredients, as is often done in alternative quantum theories. When the quantum matter field is projected to a one-particle state, the master equation for a non-relativistic quantum particle in a weak gravitational field predicts decoherence in the energy basis , in contrast to most existing theories of gravitational decoherence. We point out the gauge nature of time and space reparameterizations in matter–gravity couplings, and warn that 'intrinsic' decoherence or alternative quantum theories invoking stochastic dynamics arising from temporal or spatial fluctuations violate this fundamental symmetry of classical general relativity. Interestingly we find that the decoherence rate depends on extra parameters other than the Planck scale, an important feature of gravitational decoherence. This is similar to the dependence of the decoherence rate of a quantum Brownian particle to the temperature and spectral density of the environment it interacts with. The corresponding features when gravity acts as an environment in decohering quantum objects are what we call the ' textures' of spacetime . We point out the marked difference between the case when gravity is represented as a background spacetime versus the case when gravity acts like a thermodynamic bath to quantum particles. This points to the possibility of using gravitational decoherence measurements to discern whether gravity is intrinsically elemental or emergent.
We consider two interacting systems when one is treated classically while the other system remains quantum. Consistent dynamics of this coupling has been shown to exist, and explored in the context of treating space-time classically. Here, we prove that any such hybrid dynamics necessarily results in decoherence of the quantum system, and a breakdown in predictability in the classical phase space. We further prove that a trade-off between the rate of this decoherence and the degree of diffusion induced in the classical system is a general feature of all classical quantum dynamics; long coherence times require strong diffusion in phase-space relative to the strength of the coupling. Applying the trade-off relation to gravity, we find a relationship between the strength of gravitationally-induced decoherence versus diffusion of the metric and its conjugate momenta. This provides an experimental signature of theories in which gravity is fundamentally classical. Bounds on decoherence rates arising from current interferometry experiments, combined with precision measurements of mass, place significant restrictions on theories where Einstein's classical theory of gravity interacts with quantum matter. We find that part of the parameter space of such theories are already squeezed out, and provide figures of merit which can be used in future mass measurements and interference experiments.
We consider two interacting systems when one is treated classically while the other system remains quantum. Consistent dynamics of this coupling has been shown to exist, and explored in the context of treating space-time classically. Here, we prove that such hybrid dynamics necessarily results in decoherence of the quantum system, and a breakdown in predictability in the classical phase space. We further prove that a trade-off between the rate of this decoherence and the degree of diffusion induced in the classical system is a general feature of all classical quantum dynamics; long coherence times require strong diffusion in phase-space relative to the strength of the coupling. Applying the trade-off relation to gravity, we find a relationship between the strength of gravitationally-induced decoherence versus diffusion of the metric and its conjugate momenta. This provides an experimental signature of theories in which gravity is fundamentally classical. Bounds on decoherence rates arising from current interferometry experiments, combined with precision measurements of mass, place significant restrictions on theories where Einstein's classical theory of gravity interacts with quantum matter. We find that part of the parameter space of such theories are already squeezed out, and provide figures of merit which can be used in future mass measurements and interference experiments.
We introduce and investigate a decoherence mechanism due to quantum gravity effects. By assuming the existence of a fluctuating minimal space length scale, we derive a master equation in Lindblad form induced by the minimal-length-deformed uncertainty principle and we analyze its implications for the decoherence time and the state entropy variation. Further, we show how our model predicts a localization in energy and decoherence timescales consistent with the currently available observational evidence. Finally, we discuss schemes for the experimental verification of our model based on cavity optomechanics setups with ultracold massive molecular oscillators.