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arXiv · hep-th/9308152

On String Tunneling in Power Law Inflationary Universes

A. L. Larsen·Minos Axenides
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Abstract

We consider the evolution of circular string loops in power law expanding universes represented by a spatially flat Friedman-Robertson-Walker metric with scale factor $a(t)\propto t^p$ where $t$ is the cosmic time and $p\geq 0$. Our main result is the existence of a "magic" power $p_m=3+2\sqrt{2}$. In spacetimes with $p p_m$, however, we find additional types of solutions. They include configurations which contract from a positive initial radius to a minimal one and then expand forever. Their existence we interpret as an indication for the presence of a finite potential barrier. Equivalently the new solutions signal string nucleation and tunneling, phenomena recently shown to occur in de Sitter space.

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A. L. Larsen, Minos Axenides. 1993-08-31. On String Tunneling in Power Law Inflationary Universes. https://doi.org/10.1016/0370-2693(93)91782-i

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