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arXiv · 2208.07568

A note on the (non-)conservation of curvature perturbation

Chia-Min Lin
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Abstract

In this note, we compare two different definitions for the cosmological perturbation $\zeta$ which is conserved on large scales, and study their non-conservation on small scales. We derive an equation for the time evolution of the curvature perturbation on a uniform density slice through a calculation solely in longitudinal (conformal-Newtonian) gauge. The result is concise and compatible with that obtained via local conservation of energy-momentum tensor.

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Chia-Min Lin. 2022-08-16. A note on the (non-)conservation of curvature perturbation. https://doi.org/10.1016/j.cjph.2023.01.005

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