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arXiv · 2304.07616

Gauge/frame invariant variables for the numerical relativity study of cosmological spacetimes

Anna Ijjas
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Abstract

To numerically evolve the full Einstein equations (or modifications thereof), simulations of cosmological spacetimes must rely on a particular formulation of the field equations combined with a specific gauge/frame choice. Yet truly physical results cannot depend on the given formulation or gauge/frame choice. In this paper, we present a resolution of the gauge problem and, as an example, numerically implement it to evaluate our previous work on contracting spacetimes.

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Anna Ijjas. 2023-04-15. Gauge/frame invariant variables for the numerical relativity study of cosmological spacetimes. https://doi.org/10.1088/1475-7516%2F2023%2F06%2F061

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