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Fluctuations in the current and energy densities around a magnetic flux carrying cosmic string

L. Sriramkumar
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Abstract

We calculate the fluctuations in the current and energy densities for the case of a quantized, minimally coupled, massless, complex scalar field around a straight and infinitesimally thin cosmic string carrying magnetic flux. At zero temperature, we evaluate the fluctuations in the current and energy densities for arbitrary flux and deficit angle. At a finite temperature, we evaluate the fluctuations in the energy density for the special case wherein the flux is absent and the deficit angle equals $π$. We find that, quite generically, the dimensionless ratio of the variance to the mean-squared values of the current and energy densities are of order unity which suggests that the fluctuations around cosmic strings can be considered to be large.

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L. Sriramkumar. 2000-11-22. Fluctuations in the current and energy densities around a magnetic flux carrying cosmic string. https://doi.org/10.1088/0264-9381%2F18%2F6%2F304

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