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arXiv · 1505.02972

Dark energy and non-linear power spectrum

Sang Gyu Biern·Jinn-Ouk Gong
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Abstract

We investigate the effects of homogeneous general dark energy on the non-linear matter perturbation in fully general relativistic context. The equation for the density contrast contains even at linear order new contributions which are non-zero for general dark energy. Taking into account the next-leading-order corrections, we derive the total power spectrum in real and redshift spaces. We find that the observable galaxy power spectrum deviates from the LambdaCDM spectrum, which is nearly identical to that in the Einstein-de Sitter universe, and the relative difference is about 10% on a scale of the baryon acoustic oscillations.

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Sang Gyu Biern, Jinn-Ouk Gong. 2015-06-29. Dark energy and non-linear power spectrum. https://arxiv.org/abs/1505.02972

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