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arXiv · 0902.1084

Scale-dependent bias from primordial non-Gaussianity in general relativity

David Wands·Anze Slosar
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Abstract

In this note we examine the derivation of scale-dependent bias due to primordial non-Gaussianity of the local type in the context of general relativity. We justify the use of the Poisson equation in general relativistic perturbation theory and thus the derivation of scale-dependent bias as a test of primordial non-Gaussianity, using the spherical collapse model. The corollary is that the form of scale-dependent bias does not receive general relativistic corrections on scales larger than the Hubble radius. This leads to a formally divergent correlation function for biased tracers of the mass distribution which we discuss.

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David Wands, Anze Slosar. 2009-06-11. Scale-dependent bias from primordial non-Gaussianity in general relativity. https://doi.org/10.1103/physrevd.79.123507

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