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

Understand

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.