Stealth metastable state of scalar-tensor thermodynamics
arXiv:2203.14934 · doi:10.1103/PhysRevD.105.104006
Abstract
We investigate a puzzle in the recent thermodynamics of scalar-tensor gravity, in which general relativity is a zero-temperature state of equilibrium and scalar-tensor gravity is the non-equilibrium configuration of an effective dissipative fluid. A stealth solution of Brans-Dicke gravity with constant positive temperature is shown to be analogous to a metastable state for the effective fluid and to suffer from an instability. The stability analysis employs a version of the Bardeen-Ellis-Bruni-Hwang gauge-invariant formalism for cosmological perturbations adapted to modified gravity. The metastable state is destroyed by tensor perturbations.
An error has been corrected (main conclusion unchanged), comments added, bibliography expanded. Matches version in press in Phys. Rev. D
References in corpus (2)
Cited by in corpus (4)
- Scalar field as a perfect fluid: thermodynamics of minimally coupled scalars and Einstein frame scalar-tensor gravity
- Dynamical analysis of the covarying coupling constants in scalar-tensor gravity
- Peculiar thermal states in the first-order thermodynamics of gravity
- Past-directed scalar field gradients and scalar-tensor thermodynamics