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arXiv · 1511.09014

Rational differential forms on line and singular vectors in Verma modules over $\widehat {sl}_2$

Vadim Schechtman·Alexander Varchenko
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Abstract

We construct a monomorphism of the De Rham complex of scalar multivalued meromorphic forms on the projective line, holomorphic on the complement to a finite set of points, to the chain complex of the Lie algebra of $sl_2$-valued algebraic functions on the same complement with coefficients in a tensor product of contragradient Verma modules over the affine Lie algebra $\hat{sl}_2$. We show that the existence of singular vectors in the Verma modules (the Malikov-Feigin-Fuchs singular vectors) is reflected in the new relations between the cohomology classes of logarithmic differential forms.

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Vadim Schechtman, Alexander Varchenko. 2015-11-29. Rational differential forms on line and singular vectors in Verma modules over $\widehat {sl}_2$. https://arxiv.org/abs/1511.09014

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