Critical solutions of nonminimally coupled scalar field theory and first-order thermodynamics of gravity

  title={Critical solutions of nonminimally coupled scalar field theory and first-order thermodynamics of gravity},
  author={Valerio Faraoni and Pierre-Antoine Graham and Alexandre Leblanc},
  journal={Physical Review D},
Analytical solutions of nonminimally coupled scalar field cosmology corresponding to critical scalar field values constitute a potential challenge to the recent first-order thermodynamics of scalar-tensor gravity (a formalism picturing general relativity as the zero-temperature equilibrium state for modified gravity). The critical solutions are unstable with respect to homogeneous perturbations, hence unphysical. 
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