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arXiv · hep-th/9812003

The charge radius of a Dpbrane

Michael Gutperle·Vipul Periwal
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Abstract

Sen has shown that tachyon condensation in Dbrane-anti-Dbrane configurations can lead to remarkable connections between string theories. A consequence of his results is that there is a minimal value of the radial coordinate $r_{c} \propto \sqrt{α'} (gN)^{1/(9-p)}$ such that N units of D$p$brane charge cannot be localized to values smaller than $r_{c}.$ At this value of $r_{c}$ the curvature and the gradient of the Ramond-Ramond field strength are of order $1/α',$ and the vacuum, regarded as a Dbrane-anti-Dbrane configuration with a tachyon condensate, is rendered unstable, leading to a separation of the Dbrane and the anti-Dbrane. This value of $r_{c}$ lies in the region intermediate between the near-horizon regime and the asymptotic regime for Dbrane classical solutions for small $g$. This vacuum stability bound on the curvature can be interpreted as an uncertainty relation for Dbrane charge.

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Michael Gutperle, Vipul Periwal. 1999-02-23. The charge radius of a Dpbrane. https://doi.org/10.1088/1126-6708%2F1999%2F02%2F018

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