On the depth of separating algebras for finite groups

  • Jonathan ElmerEmail author
Original Paper


Consider a finite group G acting on a vector space V over a field \({{\Bbbk}}\) of characteristic p >  0. A separating algebra is a subalgebra A of the ring of invariants \({{{\Bbbk}[V]^G}}\) with the same point separation properties. In this article we compare the depth of an arbitrary separating algebra with that of the corresponding ring of invariants. We show that, in some special cases, the depth of A is bounded above by the depth of \({{{\Bbbk}[V]^G}}\) .


Invariant theory Separating algebra Depth Modular representation theory Cohomology modules 

Mathematics Subject Classification (2000)

13A50 (Actions of groups on commutative rings; invariant theory) 


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Copyright information

© The Managing Editors 2011

Authors and Affiliations

  1. 1.School of MathematicsUniversity of BristolBristolUK

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