Mathematische Zeitschrift

, Volume 268, Issue 1–2, pp 441–476 | Cite as

The structure of blocks with a Klein four defect group

  • David A. Craven
  • Charles W. Eaton
  • Radha Kessar
  • Markus Linckelmann


We prove Erdmann’s conjecture (J Algebra 76:505–518, 1982) stating that every block with a Klein four defect group has a simple module with trivial source, and deduce from this that Puig’s finiteness conjecture holds for source algebras of blocks with a Klein four defect group. The proof uses the classification of finite simple groups.


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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • David A. Craven
    • 1
  • Charles W. Eaton
    • 2
  • Radha Kessar
    • 3
  • Markus Linckelmann
    • 3
  1. 1.Mathematical InstituteUniversity of OxfordOxfordUK
  2. 2.School of MathematicsThe University of ManchesterManchesterUK
  3. 3.Institute of MathematicsKing’s College, University of AberdeenAberdeenScotland, UK

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