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arXiv · 2505.23924

Gauge algebra and diffeomorphisms in string field theory

Raji Ashenafi Mamade·Barton Zwiebach
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Abstract

We consider the gauge algebra of closed string field theory with a focus on diffeomorphisms. This algebra contains off-shell information in two ways. The first way is geometric, through the choice of three-punctured sphere defining the three-string vertex. We establish that to leading order in derivatives the superstring algebra is universal: identical for any choice of vertex. For bosonic strings, however, some off-shell dependence remains for vertices that require symmetrization. Off-shell information also appears because field-dependent redefinition of the gauge parameters can alter the algebra. We analyze this dependence in the language of $L_\infty$ algebras, looking at the role of trivial gauge transformations in the efforts to demonstrate that standard diffeomorphisms are part of the string gauge symmetry.

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Raji Ashenafi Mamade, Barton Zwiebach. 2025-05-29. Gauge algebra and diffeomorphisms in string field theory. https://arxiv.org/abs/2505.23924

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