Algebras and Representation Theory

, Volume 4, Issue 3, pp 293–304

Multiplicative Invariants and Semigroup Algebras

  • Martin Lorenz


Let G be a finite group acting by automorphism on a lattice A, and hence on the group algebra S=k[A]. The algebra of G-invariants in S is called an algebra of multiplicative invariants. We present an explicit version of a result of Farkas stating that multiplicative invariants of finite reflection groups are semigroup algebras.

semigroup algebra group action invariant theory reflection group root system class groups 


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Copyright information

© Kluwer Academic Publishers 2001

Authors and Affiliations

  • Martin Lorenz
    • 1
  1. 1.Department of MathematicsTemple UniversityPhiladelphiaUSA e-mail

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