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arXiv · 2206.12907

Gravitational waves at the first post-Newtonian order with the Weyssenhoff fluid in Einstein-Cartan theory

Abstract

The generation of gravitational waves from a post-Newtonian source endowed with a quantum spin, modeled by the Weyssenhoff fluid, is investigated in the context of Einstein-Cartan theory at the first post-Newtonian level by resorting to the Blanchet-Damour formalism. After having worked out the basic principles of the hydrodynamics in Einstein-Cartan framework, we study the Weyssenhoff fluid within the post-Newtonian approximation scheme. The complexity of the underlying dynamical equations suggests to employ a discrete description via the point-particle limit, a procedure which permits the analysis of inspiralling spinning compact binaries. We then provide a first application of our results by considering binary neutron star systems.

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Emmanuele Battista, Vittorio De Falco. 2022-06-26. Gravitational waves at the first post-Newtonian order with the Weyssenhoff fluid in Einstein-Cartan theory. https://doi.org/10.1140/epjc/s10052-022-10558-9

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