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arXiv · hep-ph/9707324

Effective action and motion of a cosmic string

Malcolm Anderson·Filipe Bonjour·Ruth Gregory·John Stewart
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Abstract

We examine the leading order corrections to the Nambu effective action for the motion of a cosmic string, which appear at fourth order in the ratio of the width to radius of curvature of the string. We determine the numerical coefficients of these extrinsic curvature corrections, and derive the equations of motion of the worldsheet. Using these equations, we calculate the corrections to the motion of a collapsing loop, a travelling wave, and a helical breather. From the numerical coefficients we have calculated, we discuss whether the string motion can be labelled as `rigid' or `antirigid,' and hence whether cusp or kink formation might be suppressed or enhanced.

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Malcolm Anderson, Filipe Bonjour, Ruth Gregory, John Stewart. 1997-07-11. Effective action and motion of a cosmic string. https://doi.org/10.1103/physrevd.56.8014

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