| Article | |
| Report number | arXiv:1911.09469 ; BA-TH/721-19 ; CERN-TH-2019-183 |
| Title | Generalized covariant prescriptions for averaging cosmological observables |
| Author(s) | Fanizza, Giuseppe (INFN, Pisa ; U. Lisbon (main)) ; Gasperini, Maurizio (Bari U. ; INFN, Bari) ; Marozzi, Giovanni (Pisa U. ; INFN, Pisa) ; Veneziano, Gabriele (CERN ; College de France) |
| Publication | 2020-02-14 |
| Imprint | 2019-11-21 |
| Number of pages | 29 |
| Note | 29 pages, 7 figures. Several comments added, comparison with previous results improved, references added. Version accepted for publication on JCAP |
| In: | JCAP 2002 (2020) 017 |
| DOI | 10.1088/1475-7516/2020/02/017 (publication) |
| Subject category | hep-th ; Particle Physics - Theory ; astro-ph.CO ; Astrophysics and Astronomy ; gr-qc ; General Relativity and Cosmology |
| Abstract | We present two new covariant and general prescriptions for averaging scalar observables on spatial regions typical of the observed sources and intersecting the past light-cone of a given observer. One of these prescriptions is adapted to sources exactly located on a given space-like hypersurface, the other applies instead to situations where the physical location of the sources is characterized by the experimental "spread" of a given observational variable. The geometrical and physical differences between the two procedures are illustrated by computing the averaged energy flux received by distant sources located on (or between) constant redshift surfaces, and by working in the context of a perturbed $\Lambda$CDM geometry. We find significant numerical differences (of about ten percent or more, in a large range of redshift) even limiting our model to scalar metric perturbations, and stopping our computations to the leading non-trivial perturbative order. |
| Copyright/License | preprint: (License: arXiv nonexclusive-distrib 1.0) |
Corresponding record in: Inspire
Record created 2019-11-23, last modified 2023-10-04