84 citations · 137 across the 17 of their papers we have counts for
18 papers
Black hole apparent horizons become comoving with the universe
Valerio Faraoni, Massimiliano Rinaldi
It has been shown that static black hole event horizons cannot exist in time-dependent backgrounds without becoming naked singularities. In light of this, we are left with the ques…
New interpretation of the Minkowski limit of gravity
Valerio Faraoni, Luca Gallerani, Alain Maltais-Gosselin +2
It is well-established that the Minkowski limit of pure gravity breaks down, unlike that of full Starobinsky theory . We provide a novel interpretation of t…
Laboratory rivers extremize friction and are cosmological analogues
Valerio Faraoni, Nikki Veilleux
In the shallow water approximation, the cross-sectional profiles of laboratory rivers satisfy a differential equation here shown to be formally the Friedmann equation of cosmology…
Towards a causal effective thermodynamics of scalar-tensor gravity
Narayan Banerjee, Andrea Giusti, Valerio Faraoni +2
The thermal analogy between the effective fluid of scalar-tensor gravity and Eckart's irreversible thermodynamics is extended to the causal Israel-Stewart model, adopting the minim…
The thermal view of singularity-free scalar-tensor spacetimes
Valerio Faraoni, Nikki Veilleux
The two-parameter inhomogeneous and time-dependent Pimentel solution of Brans-Dicke theory is analyzed to probe and extend the new thermal view in which General Relativity is the z…
The thermal view of cosmology
Valerio Faraoni, Santiago Novoa Cattivelli
A new thermal view of scalar-tensor gravity, in which general relativity is the zero-temperature state of gravity, is applied to the specific subclass of gravity theories an…
Thermal aspects of the anomalous limit of Brans-Dicke gravity
L. Gallerani, A. Giusti, A. Mentrelli +1
Brans-Dicke gravity does not always reduce to General Relativity in the limit for the coupling constant. This anomalous behavior is examined within the formalism of th…
Forces parallel to particle trajectories in relativistic gravity
Valerio Faraoni, Luca Valsan, Uri Gorman
Forces parallel to particle trajectories occur in physically meaningful situations, including relativistic cosmology and Einstein frame scalar-tensor gravity. These situations have…
Black hole interiors in the thermal view of scalar-tensor gravity
Valerio Faraoni
The thermal view of scalar-tensor gravity is an analogy with a dissipative fluid. The scalar degree of freedom excites gravity to a positive ``temperature'', while Einstein gravity…
Thermal origin of the attractor-to-general-relativity in scalar-tensor gravity
Valerio Faraoni, Andrea Giusti
The convergence of scalar-tensor gravity to general relativity, or the departure from it, are described in a new analogy with heat dissipation in a viscous fluid. This new thermal…
How the Schwarzschild-de Sitter horizons remain in thermal equilibrium at vastly different temperatures
Marcello Miranda, Massimiliano Rinaldi, Valerio Faraoni
The Tolman-Ehrenfest criterion of thermal equilibrium for a static fluid in a static spacetime is generalized to stationary heat conduction, in the approximation in which backreact…
Black hole event horizons are cosmologically coupled
Valerio Faraoni, Massimiliano Rinaldi
It is shown that an exactly static and spherically symmetric black hole event horizon cannot be embedded in a time-dependent geometry. Forcing it to do so results in a naked null s…
Non-geodesic timelike observers and the ultralocal limit
Reza Saadati, Luca Valsan, Valerio Faraoni
The ultralocal limit along timelike geodesics, in which any geometry reduces to Bianchi I, does not extend to non-geodesic timelike observers. Exceptions are discussed, including p…
The Tolman-Ehrenfest criterion of thermal equilibrium in scalar-tensor gravity
Numa Karolinski, Valerio Faraoni
The Tolman-Ehrenfest criterion for the thermal equilibrium of a fluid at rest in a static general-relativistic geometry is generalized to scalar-tensor gravity. Surprisingly, the g…
New phenomenology in the first-order thermodynamics of scalar-tensor gravity for Bianchi universes
Julien Houle, Valerio Faraoni
The phase space of Bianchi I universes in vacuum Brans-Dicke gravity is analyzed in terms of physical variables. The behaviour of the solutions of the field equations near the fixe…
Disforming scalar-tensor cosmology
Valerio Faraoni, Carla Zeyn
Disformal transformations of Friedmann-Lemaître-Robertson-Walker and Bianchi geometries are analyzed in the context of scalar-tensor gravity. Novel aspects discussed explicitly are…
Superinflation, quintessence, and nonsingular cosmologies
E. Gunzig, A. Saa, L. Brenig +3
The dynamics of a universe dominated by a self-interacting nonminimally coupled scalar field are considered. The structure of the phase space and complete phase portraits are given…
The gravitational interaction of light: from weak to strong fields
V. Faraoni, R. M. Dumse
An explanation is proposed for the fact that pp-waves superpose linearly when they propagate parallely, while they interact nonlinearly, scatter and form singularities or Cauchy ho…