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Comments on geometric and universal open string tachyons near fivebranes

Dan Israel
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Abstract

In a recent paper (hep-th/0703157), Sen studied unstable D-branes in NS5-branes backgrounds and argued that in the strong curvature regime the universal open string tachyon (on D-branes of the wrong dimensionality) and the geometric tachyon (on D-branes that are BPS in flat space but not in this background) may become equivalent. We study in this note an example of a non-BPS suspended D-brane vs. a BPS D-brane at equal distance between two fivebranes. We use boundary worldsheet CFT methods to show that these two unstable branes are identical.

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Dan Israel. 2007-04-25. Comments on geometric and universal open string tachyons near fivebranes. https://doi.org/10.1088/1126-6708%2F2007%2F04%2F085

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