Past-directed scalar field gradients and scalar-tensor thermodynamics

Abstract

We refine and slightly enlarge the recently proposed first-order thermodynamics of scalar-tensor gravity to include gravitational scalar fields with timelike and past-directed gradients. The implications and subtleties arising in this situation are discussed and an exact cosmological solution of scalar-tensor theory in first-order thermodynamics is revisited in light of these results.

arXiv comment7 pages, no figures

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Cited by in corpus (7)

• Scalar field as a perfect fluid: thermodynamics of minimally coupled scalars and Einstein frame scalar-tensor gravity
• More on the first-order thermodynamics of scalar-tensor and Horndeski gravity
• First-order thermodynamics of scalar-tensor gravity
• Alternative formulations of the thermodynamics of scalar-tensor theories
• Eckart heat-flux applicability in $F(\Phi ,X)R$ theories and the existence of temperature gradients
• No-Go Theorems for Hairy Black Holes in Scalar- or Vector-Tensor-Gauss-Bonnet Theory
• Thermal description of braneworld effective theories