2025/05/14 by Lavinia Heisenberg, Benedetta Rosatello, Heisenberg, Lavinia +5 · 3 citations
Physics and Astronomy · #Cosmology and Gravitation Theories #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #General Relativity and Quantum Cosmology (gr-qc) #Relativity and Gravitational Theory
paper · pdf · doi:10.48550/arxiv.2505.09544
openalex publication_date 2025/05/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Every emission of radiation in gravity also includes a nonwavelike component that leaves a permanent change in proper distances of the spacetime it travels through. This phenomenon is known as gravitational displacement memory. Building up on a recently developed computation framework that harnesses Isaacson's insights on a fundamental definition of gravitational waves, we compute the leading displacement memory formula in Einstein-Aether gravity. Our analysis represents the first direct calculation of gravitational memory in a metric theory with nontrivial asymptotic vector field value. We find that an emission of scalar and vector aether waves at a propagation speed greater than the speed of tensor radiation features unprotected causal directions with a priori unbound memory build-up. Based on the results and the existing constraint of luminally propagating tensor waves, we conjecture a stringent exclusion of the superluminal parameter space of Einstein-Aether gravity.