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arXiv · 1501.03163

Galaxy bias and gauges at second order in General Relativity

Daniele Bertacca·Nicola Bartolo·Marco Bruni·Kazuya Koyama·Roy Maartens·Sabino Matarrese·Misao Sasaki·David Wands
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Abstract

We discuss the question of gauge choice when analysing relativistic density perturbations at second order. We compare Newtonian and General Relativistic approaches. Some misconceptions in the recent literature are addressed. We show that the comoving-synchronous gauge is the unique gauge in General Relativity that corresponds to the Lagrangian frame and is entirely appropriate to describe the matter overdensity at second order. The comoving-synchronous gauge is the simplest gauge in which to describe Lagrangian bias at second order.

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Daniele Bertacca, Nicola Bartolo, Marco Bruni, Kazuya Koyama, Roy Maartens, Sabino Matarrese, Misao Sasaki, David Wands. 2015-10-06. Galaxy bias and gauges at second order in General Relativity. https://doi.org/10.1088/0264-9381%2F32%2F17%2F175019

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