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Liouville D-branes in Two-Dimensional Strings and Open String Field Theory

Debashis Ghoshal·Sunil Mukhi·Sameer Murthy
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Abstract

We study open strings in the noncritical $c=1$ bosonic string theory compactified on a circle at self-dual radius. These strings live on D-branes that are extended along the Liouville direction ({\it FZZT} branes). We present explicit expressions for the disc two- and three-point functions of boundary operators in this theory, as well as the bulk-boundary two-point function. The expressions obtained are divergent because of resonant behaviour at self-dual radius. However, these can be regularised and renormalized in a precise way to get finite results. The boundary correlators are found to depend only on the differences of boundary cosmological constants, suggesting a fermionic behaviour. We initiate a study of the open-string field theory localised to the physical states, which leads to an interesting matrix model.

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Debashis Ghoshal, Sunil Mukhi, Sameer Murthy. 2004-06-14. Liouville D-branes in Two-Dimensional Strings and Open String Field Theory. https://doi.org/10.1088/1126-6708%2F2004%2F11%2F027

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