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Tachyon condensation in unstable type I D-brane systems

O. Bergman
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Abstract

Type I string theory provides eight classes of unstable D-brane systems. We determine the gauge group and tachyon spectrum for each one, and thereby describe the gauge symmetry breaking pattern in the low-energy world-volume field theory. The topologies of the resulting coset vacuum manifolds are related to the real K-theory groups KO^{-n}, extending the known relations between the Type II classifying spaces BU and U and the complex K-theory groups K^0 and K^{-1}. We also comment on the role of the background D9-branes.

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O. Bergman. 2000-10-10. Tachyon condensation in unstable type I D-brane systems. https://doi.org/10.1088/1126-6708%2F2000%2F11%2F015

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