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A Note on Marginally Stable Bound States in Type II String Theory

Ashoke Sen
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Abstract

Spectrum of elementary string states in type II string theory contains ultra-short multiplets that are marginally stable. $U$-duality transformation converts these states into bound states at threshold of $p$-branes carrying Ramond-Ramond charges, and wrapped around $p$-cycles of a torus. We propose a test for the existence of these marginally stable bound states. Using the recent results of Polchinski and of Witten, we argue that the spectrum of bound states of $p$-branes is in agreement with the prediction of $U$-duality.

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Ashoke Sen. 1995-10-31. A Note on Marginally Stable Bound States in Type II String Theory. https://doi.org/10.1103/physrevd.54.2964

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