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arXiv · 2405.19421

String Field Theory: A Review

Ashoke Sen·Barton Zwiebach
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Abstract

As of today there exist consistent, gauge-invariant string field theories describing all string theories: bosonic open and closed strings, open superstrings, heterotic strings and type II strings. The construction of these theories require algebraic ingredients, such as $A_\infty$ and $L_\infty$ homotopy algebras, geometric ingredients, relevant to the building of moduli spaces of Riemann surfaces and the distribution of picture changing operators, and field-theoretic ingredients, involving two-dimensional CFT's and BCFT's and Batalin-Vilkovisky quantization. Applications of string field theory include the description of non-perturbative phenomena such as tachyon condensation and classical solutions, and the resolution of a number of ambiguities that bedevil the world-sheet formulation of perturbative string theory. It also allows, given a proper definition of contours of integration for momenta, for a proof of unitarity and a clear understanding of the ultraviolet finiteness of the theory. In this article we review these developments.

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Ashoke Sen, Barton Zwiebach. 2024-05-29. String Field Theory: A Review. https://arxiv.org/abs/2405.19421

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