### Abstract

There is a relatively well understood class of deformable W-algebras, resulting from Drinfeld-Sokolov (DS) type reductions of Kac-Moody algebras, which are Poisson bracket algebras based on finitely, freely generated rings of differential polynomials in the classical limit. The purpose of this paper is to point out the existence of a second class of deformable W-algebras, which in the classical limit are Poisson bracket algebras carried by infinitely, nonfreely generated rings of differential polynomials. We present illustrative examples of coset constructions, orbifold projections, as well as first class hamiltonian reductions of DS type W-algebras leading to reduced algebras with such infinitely generated classical limit. We also show in examples that the reduced quantum algebras are finitely generated due to quantum corrections arising upon normal ordering the relations obeyed by the classical generators. We apply invariant theory to describe the relations and to argue that classical cosets are infinitely, nonfreely generated in general. As a by-product, we also explain the origin of the previously constructed and so far unexplained deformable quantum W(2,4,6)- and W(2,3,4,5)-algebras.

Original language | English |
---|---|

Pages (from-to) | 409-445 |

Number of pages | 37 |

Journal | Nuclear Physics B |

Volume | 420 |

Issue number | 1-2 |

DOIs | |

Publication status | Published - May 30 1994 |

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### ASJC Scopus subject areas

- Nuclear and High Energy Physics

### Cite this

*Nuclear Physics B*,

*420*(1-2), 409-445. https://doi.org/10.1016/0550-3213(94)90388-3

**A class of W-algebras with infinitely generated classical limit.** / de Boer, J.; Fehér, L.; Honecker, A.

Research output: Contribution to journal › Article

*Nuclear Physics B*, vol. 420, no. 1-2, pp. 409-445. https://doi.org/10.1016/0550-3213(94)90388-3

}

TY - JOUR

T1 - A class of W-algebras with infinitely generated classical limit

AU - de Boer, J.

AU - Fehér, L.

AU - Honecker, A.

PY - 1994/5/30

Y1 - 1994/5/30

N2 - There is a relatively well understood class of deformable W-algebras, resulting from Drinfeld-Sokolov (DS) type reductions of Kac-Moody algebras, which are Poisson bracket algebras based on finitely, freely generated rings of differential polynomials in the classical limit. The purpose of this paper is to point out the existence of a second class of deformable W-algebras, which in the classical limit are Poisson bracket algebras carried by infinitely, nonfreely generated rings of differential polynomials. We present illustrative examples of coset constructions, orbifold projections, as well as first class hamiltonian reductions of DS type W-algebras leading to reduced algebras with such infinitely generated classical limit. We also show in examples that the reduced quantum algebras are finitely generated due to quantum corrections arising upon normal ordering the relations obeyed by the classical generators. We apply invariant theory to describe the relations and to argue that classical cosets are infinitely, nonfreely generated in general. As a by-product, we also explain the origin of the previously constructed and so far unexplained deformable quantum W(2,4,6)- and W(2,3,4,5)-algebras.

AB - There is a relatively well understood class of deformable W-algebras, resulting from Drinfeld-Sokolov (DS) type reductions of Kac-Moody algebras, which are Poisson bracket algebras based on finitely, freely generated rings of differential polynomials in the classical limit. The purpose of this paper is to point out the existence of a second class of deformable W-algebras, which in the classical limit are Poisson bracket algebras carried by infinitely, nonfreely generated rings of differential polynomials. We present illustrative examples of coset constructions, orbifold projections, as well as first class hamiltonian reductions of DS type W-algebras leading to reduced algebras with such infinitely generated classical limit. We also show in examples that the reduced quantum algebras are finitely generated due to quantum corrections arising upon normal ordering the relations obeyed by the classical generators. We apply invariant theory to describe the relations and to argue that classical cosets are infinitely, nonfreely generated in general. As a by-product, we also explain the origin of the previously constructed and so far unexplained deformable quantum W(2,4,6)- and W(2,3,4,5)-algebras.

UR - http://www.scopus.com/inward/record.url?scp=0000393649&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0000393649&partnerID=8YFLogxK

U2 - 10.1016/0550-3213(94)90388-3

DO - 10.1016/0550-3213(94)90388-3

M3 - Article

VL - 420

SP - 409

EP - 445

JO - Nuclear Physics B

JF - Nuclear Physics B

SN - 0550-3213

IS - 1-2

ER -