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arXiv · 2502.09176

On the source algebra equivalence class of blocks with cyclic defect groups, II

Abstract

This series of papers is a contribution to the program of classifying $p$-blocks of finite groups up to source algebra equivalence, starting with the case of cyclic blocks. To any $p$-block $\mathbf{B}$ of a finite group with cyclic defect group $D$, Linckelmann associated an invariant $W( \mathbf{B} )$, which is an indecomposable endo-permutation module over $D$, and which, together with the Brauer tree of $\mathbf{B}$, essentially determines its source algebra equivalence class. In Parts II-IV of our series of papers, we classify, for odd $p$, those endo-permutation modules of cyclic $p$-groups arising from $p$-blocks of quasisimple groups. In the present Part II, we reduce the desired classification for the quasisimple classical groups of Lie type $B$, $C$, and $D$ to the corresponding objective for the general linear and unitary groups; the classification is completed for the latter groups.

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BibTeXRIS

Gerhard Hiss, Caroline Lassueur. 2026-09-09. On the source algebra equivalence class of blocks with cyclic defect groups, II. https://arxiv.org/abs/2502.09176

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