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Hilbert schemes and W algebras

Wei-Ping Li·Zhenbo Qin·Weiqiang Wang
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Abstract

We construct geometrically the generating fields of a W algebra which acts irreducibly on the direct sum of the cohomology rings of the Hilbert schemes of n points on a projective surface for all n. We compute explicitly the commutators among a set of linear basis elements of the W algebra, and identify this algebra with a $W_{1+\infty}$-type algebra. A precise formula of certain Chern character operators, which is essential for the construction of the W algebra, is established in terms of the Heisenberg algebra generators. In addition, these Chern character operators are proved to be the zero-modes of vertex operators.

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Wei-Ping Li, Zhenbo Qin, Weiqiang Wang. 2002-02-26. Hilbert schemes and W algebras. https://arxiv.org/abs/math/0111047

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