The canonical compactification of a finite group of Lie type
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- by Mohan S. Putcha and Lex E. Renner PDF
- Trans. Amer. Math. Soc. 337 (1993), 305-319 Request permission
Abstract:
Let $G$ be a finite group of Lie type. We construct a finite monoid $\mathcal {M}$ having $G$ as the group of units. $\mathcal {M}$ has properties analogous to the canonical compactification of a reductive group. The complex representation theory of $\mathcal {M}$ yields Harish-Chandra’s philosophy of cuspidal representations of $G$. The main purpose of this paper is to determine the irreducible modular representations of $\mathcal {M}$. We then show that all the irreducible modular representations of $G$ come (via the 1942 work of Clifford) from the one-dimensional representations of the maximal subgroups of $\mathcal {M}$. This yields a semigroup approach to the modular representation theory of $G$, via the full rank factorizations of the ’sandwich matrices’ of $\mathcal {M}$. We then determine the irreducible modular representations of any finite monoid of Lie type.References
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Additional Information
- © Copyright 1993 American Mathematical Society
- Journal: Trans. Amer. Math. Soc. 337 (1993), 305-319
- MSC: Primary 20M30; Secondary 20G05
- DOI: https://doi.org/10.1090/S0002-9947-1993-1091231-X
- MathSciNet review: 1091231