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Tunneling in $Λ$ Decaying Cosmologies and the Cosmological Constant Problem

M. A. Jafarizadeh·F. Darabi·A. Rezaei-Aghdam·A. R. Rastegar
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Abstract

The tunneling rate, with exact prefactor, is calculated to first order in $\hbar$ for an empty closed Friedmann-Robertson-Walker (FRW) universe with decaying cosmological term $Λ\sim R^{-m}$ ($R$ is the scale factor and $m$ is a parameter $0\leq m \leq 2$). This model is equivalent to a cosmology with the equation of state $p_χ=(m/3 -1)ρ_χ$. The calculations are performed by applying the dilute-instanton approximation on the corresponding Duru-Kleinert path integral. It is shown that the highest tunneling rate occurs for $m=2$ corresponding to the cosmic string matter universe. The obtained most probable cosmological term, like one obtained by Strominger, accounts for a possible solution to the cosmological constant problem.

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M. A. Jafarizadeh, F. Darabi, A. Rezaei-Aghdam, A. R. Rastegar. 1999-05-15. Tunneling in $Λ$ Decaying Cosmologies and the Cosmological Constant Problem. https://doi.org/10.1103/physrevd.60.063514

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