Luminal propagation of gravitational waves in scalar-tensor theories: The case for torsion

0540212 - MÚ 2021 RIV US eng J - Journal Article
Barrientos, José - Cordonier-Tello, F. - Corral, C. - Izaurieta, F. - Medina, P. - Rodríguez, E. - Valdivia, O.
Luminal propagation of gravitational waves in scalar-tensor theories: The case for torsion.
Physical Review D: Particles, Fields, Gravitation and Cosmology. Roč. 100, č. 12 (2019), č. článku 124039. ISSN 1550-7998
Institutional support: RVO:67985840
Keywords : gravitational waves * scalar-tensor theory
OECD category: Pure mathematics
Impact factor: 4.833, year: 2019
Method of publishing: Limited access
https://doi.org/10.1103/PhysRevD.100.124039

Scalar-tensor gravity theories with a nonminimal Gauss-Bonnet coupling typically lead to an anomalous propagation speed for gravitational waves, and have therefore been tightly constrained by multimessenger observations such as GW170817/GRB170817A. In this paper we show that this is not a general feature of scalar-tensor theories, but rather a consequence of assuming that spacetime torsion vanishes identically. At least for the case of a nonminimal Gauss-Bonnet coupling, removing the torsionless condition restores the canonical dispersion relation and therefore the correct propagation speed for gravitational waves. To achieve this result we develop a new approach, based on the first-order formulation of gravity, to deal with perturbations on these Riemann-Cartan geometries.
Permanent Link: http://hdl.handle.net/11104/0317854