arXiv subjects

J. D. Toniato

Publications and source records attributed to J. D. Toniato.

4 recordsLinked to original sources

arXiv2019

Gravitational waves in geometric scalar gravity

We investigate the gravitational waves phenomena in the geometric scalar theory of gravity (GSG) that belongs to a class of theories such that gravity is described by a single scalar field. The associated physical metric describing the spacetime is constructed from a disformal transformation of Minkowski geometry. In this theory, a weak field approximation gives rise to a description similar to that one obtained in general relativity, although the gravitational waves in GSG have a characteristic longitudinal polarization mode, besides others modes that are observer dependent. We also analyze the energy carried by the gravitational waves as well as how their emission affects the orbital period of a binary system.

gr-qc↗

arXiv2016

More about scalar gravity

We discuss a class of models for gravity based on a scalar field. The models include and generalize the old approach by Nordström which predated and in some way inspired General Relativity. The class include also a model that we have recently introduced and discussed in its cosmological aspects (GSG). We present here a complete characterisation of the Schwarschild geometry as a vacuum solution of GSG and sketch a discussion of the first Post-Newtonian approximation.

gr-qc↗

arXiv2014

Cosmology in GSG

We describe what cosmology looks like in the context of the geometric theory of gravity (GSG) based on a single scalar field. There are two distinct classes of cosmological solutions. An interesting feature is the possibility of having a bounce without invoking exotic equations of state for the cosmic fluid. We also discuss cosmological perturbation and present the basis of structure formation by gravitational instability in the framework of the geometric scalar gravity.

gr-qc↗

arXiv2011

Hidden geometries in nonlinear theories: a novel aspect of analogue gravity

We show that non-linear dynamics of a scalar field ϕ may be described as a mod- ification of the spacetime geometry. Thus, the self-interaction is interpreted as a coupling of the scalar field with an effective gravitational metric that is constructed with ϕ itself. We prove that this process is universal, that is, it is valid for arbi- trary Lagrangian. Our results are compared to usual analogue models of gravitation, where the emergence of a metric appears as a consequence of linear perturbation.

gr-qc↗