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Overview Of K-Theory Applied To Strings

Edward Witten
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Abstract

K-theory provides a framework for classifying Ramond-Ramond (RR) charges and fields. K-theory of manifolds has a natural extension to K-theory of noncommutative algebras, such as the algebra considered in noncommutative Yang-Mills theory or in open string field theory. In a number of concrete problems, the K-theory analysis proceeds most naturally if one starts out with an infinite set of D-branes, reduced by tachyon condensation to a finite set. This suggests that string field theory should be reconsidered for N=infinity.

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Edward Witten. 2000-07-21. Overview Of K-Theory Applied To Strings. https://doi.org/10.1142/s0217751x01003822

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