Israel Journal of Mathematics

, Volume 92, Issue 1–3, pp 295–306 | Cite as

Donovan’s conjecture, crossed products and algebraic group actions



Donovan’s conjecture, on blocks of finite group algebras over an algebraically closed field of prime characteristicp, asserts that for any finitep-groupD, there are only finitely many Morita equivalence classes of blocks with defect groupD. The main result of this paper is a reduction theorem: It suffices to prove the conjecture for groups generated by conjugates ofD. A number of other finiteness results are proved along the way. The main tool is a result on actions of algebraic groups.


Equivalence Class Normal Subgroup Finite Group Algebraic Group Defect Group 


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Copyright information

© Hebrew University 1995

Authors and Affiliations

  1. 1.Institut für MathematikUniversität AugsburgAugsburgGermany

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