| Article | |
| Report number | arXiv:1812.03671 ; BA-TH/716-18 ; CERN-TH-2018-253 |
| Title | Observation angles, Fermi coordinates, and the Geodesic-Light-Cone gauge |
| Author(s) | Fanizza, Giuseppe (INFN, Pisa ; Zurich U.) ; Gasperini, Maurizio (Bari U. ; INFN, Bari) ; Marozzi, Giovanni (Pisa U. ; INFN, Pisa) ; Veneziano, Gabriele (CERN ; College de France) |
| Publication | 2019-01-03 |
| Imprint | 2018-12-10 |
| Number of pages | 14 |
| Note | 14 pages, version accepted for publication on JCAP |
| In: | JCAP 1901 (2019) 004 |
| DOI | 10.1088/1475-7516/2019/01/004 (publication) |
| Subject category | gr-qc ; General Relativity and Cosmology ; astro-ph.CO ; Astrophysics and Astronomy |
| Abstract | We show that the angular directions locally measured by a static geodesic observer in a generic cosmological background and expressed in the system of Fermi Normal Coordinates always coincide with those expressed in the Geodesic-Light-Cone (GLC) gauge, up to a local transformation which exploits the residual gauge freedom of the GLC coordinates. This is not the case for other gauges - like, for instance, the synchronous and longitudinal gauge - commonly used in the context of observational cosmology. We also make an explicit proposal for the GLC gauge-fixing condition that ensures a full identification of its angles with the observational ones. |
| Copyright/License | preprint: (License: arXiv nonexclusive-distrib 1.0) |
Corresponding record in: Inspire
Record created 2018-12-12, last modified 2023-10-04
