G. Fanizza, M. Gasperini, E. Pavone, L. Tedesco
The linearized dynamical equation for metric perturbations in a fully general, non-vacuum, background geometry is obtained from the Hamilton variational principle applied to the action up to second order. We specialize our results to the case of traceless and transverse metric fluctuations, and we discuss how the intrinsic properties of the matter stress tensor can affect (and modify) the process of gravity wave propagation even in most conventional geometric scenarios, like (for instance) those described by a FLRW metric background. We provide explicit examples for fluid, scalar field and electromagnetic field sources.
gravitational waves/theory; primordial gravitational waves (theory); cosmological perturbation theory; General Relativity and Quantum Cosmology; Astrophysics - Cosmology and Nongalactic Astrophysics; High Energy Physics - Theory
Journal of Cosmology and Astroparticle Physics
Volume 7, Issue 021, Page 18