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arXiv · 1910.02659

Modular invariants of finite gluing groups

Yin Chen·R. James Shank·David L. Wehlau
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Abstract

We use the gluing construction introduced by Jia Huang to explore the rings of invariants for a range of modular representations. We construct generating sets for the rings of invariants of the maximal parabolic subgroups of a finite symplectic group and their common Sylow $p$-subgroup. We also investigate the invariants of singular finite classical groups. We introduce parabolic gluing and use this construction to compute the invariant field of fractions for a range of representations. We use thin gluing to construct faithful representations of semidirect products and to determine the minimum dimension of a faithful representation of the semidirect product of a cyclic $p$-group acting on an elementary abelian $p$-group.

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Yin Chen, R. James Shank, David L. Wehlau. 2019-10-07. Modular invariants of finite gluing groups. https://arxiv.org/abs/1910.02659

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