2022/08/10 by José M. M. Senovilla, Senovilla, José M. M. · 2 citations
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #High Energy Physics - Theory (hep-th) #Mathematical Physics (math-ph) #Pulsars and Gravitational Waves Research
paper · pdf · doi:10.48550/arxiv.2208.05436
openalex publication_date 2022/08/10 · openalex created_date 2022/08/12 · openalex updated_date 2026/07/28
The existence of gravitational radiation arriving at null infinity -- i.e. escaping from the physical system -- is addressed in the presence of a non-negative cosmological constant Λ≥ 0. The case with vanishing Λ is well understood and relies on the properties of the News tensor field (or the News function) defined at infinity. The situation is drastically different when Λ>0 where there is no known notion of `News' with similar good properties. In this paper both situations are considered jointly from a \em tidal point of view, that is, taking into account the strength (or energy) of the curvature tensors. The fundamental object used for that purposes in the \em asymptotic (radiant) super-momentum, a causal vector defined at infinity with remarkable properties. This leads to a novel characterization of gravitational radiation valid for the general case with Λ≥ 0 that has been proven to be equivalent, when Λ=0, to the standard one based on News. The implications of this result are analyzed in some detail when Λ>0. A general procedure to construct `news tensors' when Λ>0 is depicted, a proposal for asymptotic symmetries provided, and an example of a conserved charge that may detect gravitational radiation at infinity exhibited. A series of illustrative examples is listed.