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arXiv · 0804.1131

The closed string tadpole in open string field theory

Ian Ellwood
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Abstract

We compute a class of gauge invariant observables for marginal solutions and the tachyon vacuum. In each case we find that the observables are related in a simple way to the closed-string tadpole on a disk with appropriate boundary conditions. We give a sketch of an argument that this result should hold in general using the BRST invariance of the closed string two-point function. Finally, we discuss the analogous set of invariants in the Berkovits superstring field theory.

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Ian Ellwood. 2008-04-07. The closed string tadpole in open string field theory. https://doi.org/10.1088/1126-6708%2F2008%2F08%2F063

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