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arXiv · 2409.03723

Quantum Energy Density of Cosmic Strings with Nonzero Radius

M. Koike·X. Laquidain·N. Graham
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Abstract

Zero-point fluctuations in the background of a cosmic string provide an opportunity to study the effects of topology in quantum field theory. We use a scattering theory approach to compute quantum corrections to the energy density of a cosmic string, using the "ballpoint pen" and "flowerpot" models to allow for a nonzero string radius. For computational efficiency, we consider a massless field in $2+1$ dimensions. We show how to implement precise and unambiguous renormalization conditions in the presence of a deficit angle, and make use of Kontorovich-Lebedev techniques to rewrite the sum over angular momentum channels as an integral on the imaginary axis.

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M. Koike, X. Laquidain, N. Graham. 2024-09-05. Quantum Energy Density of Cosmic Strings with Nonzero Radius. https://doi.org/10.1103/physrevd.110.105009

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