43 citations · 183 across the 15 of their papers we have counts for
11 papers · 1 filter
Dynamical system analysis of the cosmological phases in Palatini -essence gravity
Fabio Moretti, Flavio Bombacigno
We formulate a generalized -essence model in the presence of a Palatini gravitational sector. In the corresponding biscalar-tensor theory, we discuss the distin…
Gravitational waves in Palatini gravity for a non-minimal geometry-matter coupling
Flavio Bombacigno, Fabio Moretti, Gonzalo J. Olmo
We discuss the propagation of gravitational waves over a non-Riemannian spacetime, when a non-minimal coupling between the geometry and matter is considered in the form of contract…
Landau damping for gravitational waves in parity-violating theories
Flavio Bombacigno, Fabio Moretti, Simon Boudet +1
We discuss how tensor polarizations of gravitational waves can suffer Landau damping in the presence of velocity birefringence, when parity symmetry is explicitly broken. In partic…
Torsional birefringence in metric-affine Chern-Simons gravity: gravitational waves in late-time cosmology
S. Boudet, F. Bombacigno, F. Moretti +1
In the context of the metric-affine Chern-Simons gravity endowed with projective invariance, we derive analytical solutions for torsion and nonmetricity in the homogeneous and isot…
Linear analysis of the gravitational beam-plasma instability
Fabio Moretti, Matteo Del Prete, Giovanni Montani
We investigate the well-known phenomenon of the beam-plasma instability in the gravitational sector, when a fast population of particles interacts with the massive scalar mode of a…
The role of longitudinal polarizations in Horndeski and macroscopic gravity: Introducing gravitational plasmas
Fabio Moretti, Flavio Bombacigno, Giovanni Montani
We discuss some general and relevant features of longitudinal gravitational modes in Horndeski gravity and their interaction with matter media. Adopting a gauge-invariant formulati…
Gravitational Landau Damping for massive scalar modes
Fabio Moretti, Flavio Bombacigno, Giovanni Montani
We establish the possibility of Landau damping for gravitational scalar waves which propagate in a non-collisional gas of particles. In particular, under the hypothesis of homogene…
Scalar modes in extended hybrid metric-Palatini gravity: weak field phenomenology
Flavio Bombacigno, Fabio Moretti, Giovanni Montani
We investigate the nature of additional scalar degrees of freedom contained in extended hybrid metric-Palatini gravity, outlining the emergence of two coupled dynamical scalar mode…
Gravitational waves in a molecular medium: dispersion, extra polarizations and quantitative estimates
Fabio Moretti, Giovanni Montani
We analyze the propagation of gravitational waves in a molecular matter medium: our findings demonstrate that dispersion only is expected, together with the emergence of three extr…
Gauge invariant formulation of gravitational waves in metric gravity
Fabio Moretti, Flavio Bombacigno, Giovanni Montani
We analyze the gravitational waves propagation in metric theories of gravity. In particular, adopting a gauge invariant formalism we clearly determine the exact propagating…
Modified Gravitational Waves Across Galaxies from Macroscopic Gravity
Giovanni Montani, Fabio Moretti
We analyze the propagation of gravitational waves in a medium containing bounded subsystems ("molecules"), able to induce significant Macroscopic Gravity effects. We establish a pr…