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arXiv · 1306.6532

Numerical Solutions of Open String Field Theory in Marginally Deformed Backgrounds

Isao Kishimoto·Tomohiko Takahashi
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Abstract

We investigate numerical solutions of bosonic open string field theory in some marginally deformed backgrounds, which are obtained by expanding the action around an identity-based marginal solution with one parameter. We construct numerical solutions in the Siegel gauge and the Landau gauge corresponding to the tachyon vacuum. Their vacuum energy approximately cancels the D-brane tension for larger intervals of the parameter with increasing truncation level. The result is consistent with the previous expectation that the identity-based marginal solution has vanishing energy regardless of the values of the parameter. We also study the marginal branch (M-branch) and the vacuum branch (V-branch) and evaluate not only the vacuum energy but also the gauge invariant overlaps with the graviton and the closed tachyon. We observe that there is a finite bound for the value of the massless field of numerical solutions even in the marginally deformed background.

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Isao Kishimoto, Tomohiko Takahashi. 2013-06-27. Numerical Solutions of Open String Field Theory in Marginally Deformed Backgrounds. https://doi.org/10.1093/ptep/ptt072

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