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arXiv · 1010.4125

Closed String Cohomology in Open String Field Theory

Nicolas Moeller·Ivo Sachs
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Abstract

We show that closed string states in bosonic string field theory are encoded in the cyclic cohomology of cubic open string field theory (OSFT) which, in turn, classifies the deformations of OSFT. This cohomology is then shown to be independent of the open string background. Exact elements correspond to closed string gauge transformations, generic boundary deformations of Witten's 3-vertex and infinitesimal shifts of the open string background. Finally it is argued that the closed string cohomology and the cyclic cohomology of OSFT are isomorphic to each other.

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Nicolas Moeller, Ivo Sachs. 2010-10-20. Closed String Cohomology in Open String Field Theory. https://doi.org/10.1007/jhep07(2011)022

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