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arXiv · 2212.03573

Incompatibility of Standard Galaxy Bias Models in General Relativity

Jaiyul Yoo
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Abstract

The standard model for galaxy bias is built in a Newtonian framework, and several attempts have been made in the past to put it in a relativistic framework. The focus of past works was, however, to use the same Newtonian formulation, but to provide its interpretation in a relativistic framework by either fixing a gauge condition or transforming to a local coordinate system. Here we demonstrate that these reverse-engineered approaches do not respect the diffeomorphism symmetry in general relativity, and we need to develop a covariant model of galaxy bias that is diffeomorphism compatible. We consider a simple toy model for galaxy bias and discuss the impact for measuring the primordial non-Gaussianity.

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Jaiyul Yoo. 2022-12-07. Incompatibility of Standard Galaxy Bias Models in General Relativity. https://doi.org/10.1088/1475-7516%2F2023%2F10%2F054

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