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arXiv · 1306.5131

Two-point correlation function of density perturbations in a large void universe

Ryusuke Nishikawa·Chul-Moon Yoo·Ken-ichi Nakao
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Abstract

We study the two-point correlation function of density perturbations in a spherically symmetric void universe model which does not employ the Copernican principle. First we solve perturbation equations in the inhomogeneous universe model and obtain density fluctuations by using a method of non-linear perturbation theory which was adopted in our previous paper. From the obtained solutions, we calculate the two-point correlation function and show that it has a local anisotropy at the off-center position differently from those in homogeneous and isotropic universes. This anisotropy is caused by the tidal force in the off-center region of the spherical void. Since no tidal force exists in homogeneous and isotropic universes, we may test the inhomogeneous universe by observing statistical distortion of the two-point galaxy correlation function.

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Ryusuke Nishikawa, Chul-Moon Yoo, Ken-ichi Nakao. 2013-06-21. Two-point correlation function of density perturbations in a large void universe. https://doi.org/10.1103/physrevd.88.123520

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