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On the Casimir energy of a massive scalar field in positive curvature space

E Elizalde·A C Tort
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Abstract

We re-evaluate the zero point Casimir energy for the case of a massive scalar field in $\mathbf{R}^{1}\times\mathbf{S}^{3}$ space, allowing also for deviations from the standard conformal value $ξ=1/6$, by means of zero temperature zeta function techniques. We show that for the problem at hand this approach is equivalent to the high temperature regularisation of the vacuum energy.

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E Elizalde, A C Tort. 2003-11-13. On the Casimir energy of a massive scalar field in positive curvature space. https://arxiv.org/abs/hep-th/0311114

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