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Ward Identities in Two-Dimensional String Theory

Igor R. Klebanov
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Abstract

I study the Ward identities of the $w_\infty$ symmetry of the two-dimensional string theory. It is found that, not just an isolated vertex operator, but also a number of vertex operators colliding at a point can produce local charge non-conservation. The structure of all such contact terms is determined. As an application, I calculate all the non-vanishing bulk tachyon amplitudes directly through the Ward identities for a Virasoro subalgebra of the $w_\infty$.

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Igor R. Klebanov. 1992-01-03. Ward Identities in Two-Dimensional String Theory. https://doi.org/10.1142/s0217732392000690

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