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Renormalization Group Flow in BRST Invariant Open String $σ$-Model

Rui Neves
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Abstract

The renormalization group flow in the theory space of a BRST invariant string $σ$-model is investigated. For the open bosonic string the non-perturbative off-shell effective action and its gauge symmetry properties are determined from $β$-functions defined by the local Weyl anomaly. The interactions are shown to explicitly break the free theory BRST invariance generating new non-linear gauge symmetries of the type present in Witten's string field theory. In the Feynman-Siegel gauge the $σ$-model is shown to generate Witten's structure of vertex couplings.

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Rui Neves. 2000-08-02. Renormalization Group Flow in BRST Invariant Open String $σ$-Model. https://arxiv.org/abs/hep-th/0008026

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