Conservative entropic forces

Abstract

Entropic forces have recently attracted considerable attention as ways to reformulate, retrodict, and perhaps even "explain'" classical Newtonian gravity from a rather specific thermodynamic perspective. In this article I point out that if one wishes to reformulate classical Newtonian gravity in terms of an entropic force, then the fact that Newtonian gravity is described by a conservative force places significant constraints on the form of the entropy and temperature functions. (These constraints also apply to entropic reinterpretations of electromagnetism, and indeed to any conservative force derivable from a potential.) The constraints I will establish are sufficient to present real and significant problems for any reasonable variant of Verlinde's entropic gravity proposal, though for technical reasons the constraints established herein do not directly impact on either Jacobson's or Padmanabhan's versions of entropic gravity. In an attempt to resolve these issues, I will extend the usual notion of entropic force to multiple heat baths with multiple "temperatures'" and multiple "entropies".

V1: 21 pages; no figures. V2: now 24 pages. Two new sections (reduced mass formulation, decoherence). Many small clarifying comments added throughout the text. Several references added. V3: Three more references added. V4: now 25 pages. Some extra discussion on the relation between Verlinde's scenario and the Jacobson and Padmanabhan scenarios. This version accepted for publication in JHEP

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Cited by in corpus (34)

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• Generalizing the running vacuum energy model and comparing with the entropic-force models
• Friedmann equations from emergence of cosmic space
• Corrections to Friedmann equations inspired by Kaniadakis entropy
• Entropic force approach to noncommutative Schwarzschild black holes signals a failure of current physical ideas
• Generalized thermodynamic constraints on holographic-principle-based cosmological scenarios
• Condensation of an ideal gas with intermediate statistics on the horizon
• Inconsistencies in Verlinde's emergent gravity
• Entropic force approach in a noncommutative charged black hole and the equivalence principle
• On burning a lump of coal
• Exploring the Nature of Gravity
• Heat capacity of Holographic screen inspires MOND theory
• Varying constants entropic--$\Lambda$CDM cosmology
• Deformed Horava-Lifshitz Cosmology and Stability of Einstein Static Universe
• Relativistic quantum information as radiation reaction: entanglement entropy and self-force of a moving mirror analog to the CGHS black hole
• Cosmological Constraints on Entropic Cosmology with Matter Creation
• Decoherence-Free Entropic Gravity: Model and Experimental Tests
• On entropic gravity: the entropy postulate, entropy content of screens and relation to quantum mechanics
• Big-Bang nucleosynthesis constraints on (dual) Kaniadakis cosmology
• Maximally Symmetric Spacetimes emerging from thermodynamic fluctuations
• Thermodynamical features of Verlinde's approach for a non-commutative Schwarzschild-anti-deSitter black hole in a broad range of scales
• MOND Theory and Thermodynamics of Spacetime
• Entropic gravity versus gravitational pseudotensors in static spherically symmetric spacetimes
• Quantum black holes as classical space factories
• Modified gravity/entropic gravity correspondence due to graviton mass
• Hydrostatic mass of galaxy clusters within some theories of gravity
• q-Path entropy phenomenology for phase-space curves
• Implications of maximum acceleration on dynamics
• Decoherence-Free Entropic Gravity for Dirac Fermion
• Depletion force between disordered linear macromolecules
• The $\mu$-deformed Einstein field equations with $\mu$-dependent effective cosmological constant
• From mindless mathematics to thinking meat?
• Entropic force law in the presence of a noncommutative inspired spacetime for a solar system scale
• Gravitational thermodynamics and universal holographic duality in dynamical spacetimes