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arXiv · 2412.15139

On the perturbed Friedmann equations in Newtonian Gauge

Jaume de Haro·Emilio Elizalde·Supriya Pan
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Abstract

Based on the Newtonian mechanics, in this article, we present a heuristic derivation of the Friedmann equations, providing an intuitive foundation for these fundamental relations in cosmology. Additionally, using the first law of thermodynamics and Euler's equation, we derive a set of equations that, at linear order, coincide with those obtained from the conservation of the stress-energy tensor in General Relativity. This approach not only highlights the consistency between Newtonian and relativistic frameworks in certain limits but also serves as a pedagogical bridge, offering insights into the physical principles underlying the dynamics of the universe.

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Jaume de Haro, Emilio Elizalde, Supriya Pan. 2024-12-19. On the perturbed Friedmann equations in Newtonian Gauge. https://arxiv.org/abs/2412.15139

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