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arXiv · 1605.00159

Dynamics of self-interacting strings and energy-momentum conservation

Kurt Lechner
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Abstract

Classical strings coupled to a metric, a dilaton and an axion, as conceived by superstring theory, suffer from ultraviolet divergences due to self-interactions. Consequently, as in the case of radiating charged particles, the corresponding effective string dynamics can not be derived from an action principle. We propose a fundamental principle to build this dynamics, based on local energy-momentum conservation in terms of a well-defined distribution-valued energy-momentum tensor. Its continuity equation implies a finite equation of motion for self-interacting strings. The construction is carried out explicitly for strings in uniform motion in arbitrary space-time dimensions, where we establish cancelations of ultraviolet divergences which parallel superstring non-renormalization theorems. The uniqueness properties of the resulting dynamics are analyzed.

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Kurt Lechner. 2016-04-30. Dynamics of self-interacting strings and energy-momentum conservation. https://doi.org/10.1016/j.aop.2017.05.024

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