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Extended N=2 Superconformal Structure of Gravity and W-Gravity Coupled to Matter

M. Bershadsky·W. Lerche·D. Nemeschansky·N. P. Warner
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Abstract

We show that almost all string theories, including the bosonic string, the superstring and $W$-string theories, possess a twisted N=2 superconformal symmetry. This enables us to establish a connection between topological gravity and the field theoretical description of matter coupled to gravity. We also show how the \brs operators of the $W_n$-string can be obtained by hamiltonian reduction of $SL(n|n-1)$. The tachyonic and ground ring states of $W$-strings are described in the light of the N=2 superconformal structure, and the ground ring generators for the non-critical $W_3$-string are explicitly constructed. The relationship to $G/G$ models and quantum integrable systems is also briefly described.

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M. Bershadsky, W. Lerche, D. Nemeschansky, N. P. Warner. 1992-12-09. Extended N=2 Superconformal Structure of Gravity and W-Gravity Coupled to Matter. https://doi.org/10.1016/0550-3213(93)90306-a

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