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arXiv · 1309.6950

Ray tracing in FLRW flat space-times

Giovanni Acquaviva·Luca Bonetti·Guido Cognola·Sergio Zerbini
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Abstract

In this work we take moves from the debate triggered by Melia et al [9]. and followed by opposite comments by Lewis and Oirschot [10,11]. The point in question regards the role of the Hubble horizon as a limit for observability in a cosmological setting. We propose to take the issue in a broader way by relating it to the causal character of the Hubble surface and to the tracing of null trajectories, focusing on both three-fluids and generalized Chaplygin gas models. The results should make clear that light rays reaching a comoving observer at R(t_0)=0 have never travelled a distance greater than the areal radius of the horizon until t_0.

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Giovanni Acquaviva, Luca Bonetti, Guido Cognola, Sergio Zerbini. 2013-09-26. Ray tracing in FLRW flat space-times. https://doi.org/10.1103/physrevd.88.124024

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