Defect zero p-blocks for finite simple groups

  title={Defect zero p-blocks for finite simple groups},
  author={Andrew Granville and Ken Ono},
  journal={Transactions of the American Mathematical Society},
  • A. Granville, K. Ono
  • Published 1 December 1996
  • Mathematics
  • Transactions of the American Mathematical Society
We classify those finite simple groups whose Brauer graph (or decomposition matrix) has a p-block with defect 0, completing an investigation of many authors. The only finite simple groups whose defect zero p-blocks remained unclassified were the alternating groups An. Here we show that these all have a p-block with defect 0 for every prime p ≥ 5. This follows from proving the same result for every symmetric group Sn, which in turn follows as a consequence of the t-core partition conjecture… 

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