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arXiv · 1908.06023

The physical origin of the cosmological constant: continuum limit and the analogy with the Casimir effect

Stefano Viaggiu
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Abstract

In this paper we continue the investigations in \cite{1} concerning the origin of the cosmological constant. First of all, we generalise the results in \cite{1,2} by considering a continuum approximation for a radiation field in a cosmological background. In this way, we clearly show that the bare cosmological constant is obtained with wanishing temperature $T$ and that the specific heat $C$ is zero at the decoherence scale $L_D$. Moreover, we address the issue to fix the parameters present in our model. In particular, we push forward the analogy between our expression for $Λ_L$ at a given proper scale $L$ and the one extrapolated by the Casimir effect. As a consequence, we can fix the decoherence scale $L_D$ at which we have the crossover to classicality to be of the order of $\sim 10^{-5}$ meters. This implies that the actual observed value of the cosmological constant is fixed (frozen) at this new physical scale.

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Stefano Viaggiu. 2019-08-22. The physical origin of the cosmological constant: continuum limit and the analogy with the Casimir effect. https://doi.org/10.1088/1402-4896%2Fab3d02

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