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Casimir Energy of the Universe and the Dark Energy Problem

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 Added by Shoichi Ichinose
 Publication date 2012
  fields Physics
and research's language is English




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We regard the Casimir energy of the universe as the main contribution to the cosmological constant. Using 5 dimensional models of the universe, the flat model and the warped one, we calculate Casimir energy. Introducing the new regularization, called {it sphere lattice regularization}, we solve the divergence problem. The regularization utilizes the closed-string configuration. We consider 4 different approaches: 1) restriction of the integral region (Randall-Schwartz), 2) method of 1) using the minimal area surfaces, 3) introducing the weight function, 4) {it generalized path-integral}. We claim the 5 dimensional field theories are quantized properly and all divergences are renormalized. At present, it is explicitly demonstrated in the numerical way, not in the analytical way. The renormalization-group function ($be$-function) is explicitly obtained. The renormalization-group flow of the cosmological constant is concretely obtained.



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Casimir energy is calculated for 5D scalar theory in the {it warped} geometry. A new regularization, called {it sphere lattice regularization}, is taken. The regularized configuration is {it closed-string like}. We numerically evaluate $La$(4D UV-cutoff), $om$(5D bulk curvature, extra space UV-boundary parameter) and $T$(extra space IR-boundary parameter) dependence of Casimir energy. 5D Casimir energy is {it finitely} obtained after the {it proper renormalization procedure.} The {it warp parameter} $om$ suffers from the {it renormalization effect}. Regarding Casimir energy as the main contribution to the cosmological term, we examine the dark energy problem.
371 - Joshua Frieman 2008
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