English

An alternative approach to modelling a cosmic void and its effect on the cosmic microwave background

Cosmology and Nongalactic Astrophysics 2019-07-31 v1 General Relativity and Quantum Cosmology

Abstract

We apply our tetrad-based approach for constructing spherically-symmetric solutions in general relativity to modelling a void, and compare it with the standard Lema\^itre-Tolman-Bondi (LTB) formalism. In particular, we construct models for the void observed in the direction of Draco in the WISE-2MASS galaxy survey, and a corresponding cosmic microwave background (CMB) temperature decrement in the Planck data in the same direction. We find that the present-day density and velocity profiles of the void are not well constrained by the existing data, so that void models produced from the two approaches can differ substantially while remaining broadly consistent with the observations. We highlight the importance of considering the velocity as well as the density profile in constraining voids.

Keywords

Cite

@article{arxiv.1804.02927,
  title  = {An alternative approach to modelling a cosmic void and its effect on the cosmic microwave background},
  author = {Do Young Kim and Anthony N. Lasenby and Michael P. Hobson},
  journal= {arXiv preprint arXiv:1804.02927},
  year   = {2019}
}

Comments

12 pages, 14 figures, submitted to MNRAS