242 citations · 2.5k across the 69 of their papers we have counts for
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A new approach to the thermodynamics of scalar-tensor gravity
Valerio Faraoni, Andrea Giusti, Andrea Mentrelli
We discuss and expand a new approach to the thermodynamics of scalar-tensor gravity and its diffusion toward general relativity (seen as an equilibrium state) proposed in a previou…
Orbits in bootstrapped Newtonian gravity
Anna D'Addio, Roberto Casadio, Andrea Giusti +1
Bootstrapped Newtonian gravity is a non-linear version of Newton's law which can be lifted to a fully geometric theory of gravity starting from a modified potential. Here, we study…
On the fractional Laplacian of variable order
Eric Darve, Marta D'Elia, Roberto Garrappa +2
We present a novel definition of variable-order fractional Laplacian on Rn based on a natural generalization of the standard Riesz potential. Our definition holds for values of the…
First-order thermodynamics of Horndeski gravity
Andrea Giusti, Stefan Zentarra, Lavinia Heisenberg +1
We extend to the Horndeski realm the irreversible thermodynamics description of gravity previously studied in "first generation" scalar-tensor theories. We identify a subclass of H…
A quantum state for the late Universe
Andrea Giusti, Silvia Buffa, Lavinia Heisenberg +1
We consider the quantum description of a toy model universe in which the Schwarzschild-de Sitter geometry emerges from the coherent state of a massless scalar field. Although highl…
Modified Gravity and Cosmology: An Update by the CANTATA Network
Emmanuel N. Saridakis, Ruth Lazkoz, Vincenzo Salzano +50
General Relativity and the CDM framework are currently the standard lore and constitute the concordance paradigm. Nevertheless, long-standing open theoretical issues, as well as…
Analogies between logistic equation and relativistic cosmology
Steve Dussault, Valerio Faraoni, Andrea Giusti
We develop several formal analogies between the logistic equation and the spatially homogeneous and isotropic relativistic cosmology described by the Einstein-Friedmann equations.…
Thermodynamics of scalar-tensor gravity
Valerio Faraoni, Andrea Giusti
Previously, the Einstein equation has been described as an equation of state, general relativity as the equilibrium state of gravity, and gravity as a non-equilibrium…
Effective metric outside bootstrapped Newtonian sources
Roberto Casadio, Andrea Giusti, Iberê Kuntz +1
We determine the complete space-time metric from the bootstrapped Newtonian potential generated by a static spherically symmetric source in the surrounding vacuum. This metric cont…
Variable-order fractional calculus: a change of perspective
Roberto Garrappa, Andrea Giusti, Francesco Mainardi
Several approaches to the formulation of a fractional theory of calculus of "variable order" have appeared in the literature over the years. Unfortunately, most of these proposals…
Spherical inhomogeneous solutions of Einstein and scalar-tensor gravity: a map of the land
Valerio Faraoni, Andrea Giusti, Bardia H. Fahim
We review spherical and inhomogeneous analytic solutions of the field equations of Einstein and of scalar-tensor gravity, including Brans-Dicke theory, non-minimally (possibly conf…