CMB dipoles and other low-order multipoles in the quasispherical Szekeres model
Abstract
Several authors have previously shown that a Gpc-scale void based on the spherically symmetric Lemaître-Tolman-Bondi (LTB) model can provide a good fit to certain cosmological data, including the SNIa data, but it is only consistent with the observed CMB dipole if we are located very close to the center, in violation of the Copernican principle. In this work we investigate the more general quasispherical Szekeres model, which does not include spherical symmetry, in order to determine whether this option may be less constricting. We find that the observer is still constrained to a small region, but it is not as geometrically “special” as the center of a LTB void. Furthermore, whereas the quadrupole and octupole near the center of a LTB void are necessarily small, certain Szekeres models can include a significant quadrupole while still being consistent with the observed dipole, hinting that Szekeres models may be able to give an explanation for the observed quadrupole/octupole anomalies.
- Publication:
-
Physical Review D
- Pub Date:
- January 2013
- DOI:
- 10.1103/PhysRevD.87.023524
- arXiv:
- arXiv:1907.08684
- Bibcode:
- 2013PhRvD..87b3524B
- Keywords:
-
- 98.80.-k;
- 04.20.Jb;
- 98.65.Dx;
- 98.80.Es;
- Cosmology;
- Exact solutions;
- Superclusters;
- large-scale structure of the Universe;
- Observational cosmology;
- Astrophysics - Cosmology and Nongalactic Astrophysics;
- General Relativity and Quantum Cosmology
- E-Print:
- 14 pages, 8 figures, originally published in Phys. Rev. D in 2013