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Half-strings, Projectors, and Multiple D-branes in Vacuum String Field Theory

Leonardo Rastelli·Ashoke Sen·Barton Zwiebach
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Abstract

A sliver state is a classical solution of the string field theory of the tachyon vacuum that represents a background with a single D25-brane. We show that the sliver wavefunctional factors into functionals of the left and right halves of the string, and hence can be naturally regarded as a rank-one projector in a space of half-string functionals. By developing an algebraic oscillator approach we are able construct higher rank projectors that describe configurations of multiple D-branes of various dimensionalities and located at arbitrary positions. The results bear remarkable similarities with non-commutative solitons.

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Leonardo Rastelli, Ashoke Sen, Barton Zwiebach. 2001-05-07. Half-strings, Projectors, and Multiple D-branes in Vacuum String Field Theory. https://doi.org/10.1088/1126-6708%2F2001%2F11%2F035

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