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On cosmological perturbations in FRW model with scalar field and false vacuum decay

Arsen Khvedelidze·George Lavrelashvili·Takahiro Tanaka
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Abstract

The unconstrained reduced action corresponding to the dynamics of scalar fluctuations about the Friedmann-Robertson-Walker (FRW) background is derived using Dirac's method of description of singular Lagrangian systems. The results are applied to so-called negative mode problem in description of tunneling transitions with gravity. With our special choice of physical variable, the kinetic term of the reduced action has a conventional signature for a wide class of models. In this representation, the existence of a negative mode justifying the false vacuum decay picture turns out to be manifest. We also explain how the present result becomes consistent with the previously proved ``no negative mode (supercritical supercurvature mode) theorem''.

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Arsen Khvedelidze, George Lavrelashvili, Takahiro Tanaka. 2000-08-23. On cosmological perturbations in FRW model with scalar field and false vacuum decay. https://doi.org/10.1103/physrevd.62.083501

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