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arXiv · 2001.09889

Redshift and gauge choice

Harald Skarke
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Abstract

We show that a specific gauge choice comes extremely close to defining a frame whose preferred observers see a dipole-free CMB. In this gauge the metric is the product of a scale factor depending on all spacetime coordinates, and a metric featuring an expansion-free geodesic timelike vector field. This setup facilitates the computation of redshift and other distance measures and explains why we can have a highly isotropic CMB despite large inhomogeneities.

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Harald Skarke. 2020-01-27. Redshift and gauge choice. https://doi.org/10.1103/physrevd.102.123520

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