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arXiv · 0801.2950

Classical stability of a homogeneous, anisotropic inflating space-time

Timothy R. Dulaney·Moira I. Gresham·Mark B. Wise
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Abstract

We study the classical stability of an anisotropic space-time seeded by a spacelike, fixed norm, dynamical vector field in a vacuum-energy-dominated inflationary era. It serves as a model for breaking isotropy during the inflationary era. We find that, for a range of parameters, the linear differential equations for small perturbations about the background do not have a growing mode. We also examine the energy of fluctuations about this background in flat-space. If the kinetic terms for the vector field do not take the form of a field strength tensor squared then there is a negative energy mode and the background is unstable. For the case where the kinetic term is of the form of a field strength tensor squared we show that perturbations about the background have positive energy at lowest order.

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Timothy R. Dulaney, Moira I. Gresham, Mark B. Wise. 2008-11-13. Classical stability of a homogeneous, anisotropic inflating space-time. https://doi.org/10.1103/physrevd.77.083510%2010.1103%2Fphysrevd.79.029903

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