2007/09/20 by Barak Kol, Kol, Barak
Physics and Astronomy · #Advanced Differential Geometry Research #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) #gr-qc #hep-th
paper · pdf · doi:10.48550/arxiv.0709.3254
10 pages, 1 figure. This paper is not intended to be submitted to a refereed journal as explained at the end of the introduction
arxiv created 2007/09/20 · openalex publication_date 2007/09/20 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
It is shown that perturbations around backgrounds with one non-homogeneous dimension, namely of co-homogeneity 1, can be canonically simplified, a property that is shown to hold to any order in perturbation theory. Recalling that the problem naturally reduces to 1d, a procedure is described whereby for each gauge function in 1d two 1d fields are eliminated from the action - one is gauge and can be eliminated without a constraint and the other is auxiliary. These results generalize the results of hep-th/0609001 from linear to non-linear perturbations and they unify two cases of physical interest: cosmological perturbations and perturbations to static spherically symmetric backgrounds. An application to black strings is discussed in some detail.