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Effect of Void Network on CMB Anisotropy

Nobuyuki Sakai·Naoshi Sugiyama·Jun'ichi Yokoyama
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Abstract

We study the effect of a void network on the CMB anisotropy in the Einstein-de Sitter background using Thompson &Vishniac's model. We consider comprehensively the Sacks-Wolfe effect, the Rees-Sciama effect and the gravitational lensing effect. Our analysis includes the model of primordial voids existing at recombination, which is realized in some inflationary models associated with a first-order phase transition. If there exist primordial voids whose comoving radius is larger than $\sim10h^{-1}$Mpc at recombination, not only the Sachs-Wolfe effect but also the Rees-Sciama effect is appreciable even for multipoles $l\lsim1000$ of the anisotropy spectrum. The gravitational lensing effect, on the other hand, slightly smoothes the primary anisotropy; quantitatively, our results for the void model are similar to the previous results for a CDM model. All the effects, together, would give some constraints on the configuration or origin of voids with high-resolution data of the CMB anisotropy.

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Nobuyuki Sakai, Naoshi Sugiyama, Jun'ichi Yokoyama. 1998-11-08. Effect of Void Network on CMB Anisotropy. https://doi.org/10.1086/306550

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