Invariants of Finite Groups over Finite Fields: Recent Progress and New Conjectures

  • Peter Fleischmann


Let G be a finite group acting on a polynomial ring A:= F[x1,…, xn] by graded algebra automorphisms. If F is a field of characteristic zero, then due to classical results of Emmy Noether one knows that the invariant ring A G can be generated in degrees less or equal to |G|. If F is a field of positive characteristic p dividing the group order |G|, this is no longer true. The situation in characteristic p not dividing |G| has been clarified recently after being open for several decades. This paper presents an account on these developments, including some related questions and conjectures dealing with constructive and structural properties of modular invariant rings.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • Peter Fleischmann
    • 1
  1. 1.Institute of Mathematics and StatisticsUniversity of Kent at CanterburyCanterburyEngland

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