User Jim Humphreys

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Modular reductions of simple characters

answered May 7, 2013 at 23:07

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Why are these parabolic subgroups opposed?

answered Jun 3, 2013 at 14:23

4 votes

Idempotents and Structure of Simple GL(n,p) modules in the describing characteristic

answered Nov 3, 2014 at 17:02

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How do I show that a separable isogeny is central?

answered Jul 27, 2014 at 13:43

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Representations of $\mathrm{SL}(2)$ in characteristic 2

answered Feb 25, 2014 at 16:12

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The action of the center on the extended Dynkin diagram

answered Mar 10, 2015 at 22:43

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A natural bijection between the orbit spaces of $p$-nilpotent matrices for varying $p$

answered Jan 9, 2015 at 0:06

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quasicrystal and penrose tiling, mathematical introduction

answered Jan 9, 2015 at 1:37

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Representation Theory of Lie Groups: Reference Request

answered May 7, 2015 at 12:49

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Connected components of algebraic groups

answered Mar 24, 2015 at 22:21

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Root in positive Weyl chamber

answered Mar 28, 2015 at 16:31

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A subgroup of the Weyl group

answered Aug 23, 2013 at 17:10

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Reference for embeddings of reflection groups (related to folding ADE Coxeter graphs)?

answered Jul 30, 2013 at 17:33

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Computing relative Lie algebra cohomology (as appears in Borel-Weil-Bott theorem)

answered Jun 30, 2013 at 18:12

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Hilbert's Finiteness Theorem for connected semisimple Lie groups in Weyl's "Classical Groups"

answered Jul 3, 2013 at 13:02

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Dimension of the nilpotent centralizer of a nilpotent matrix

answered Mar 20, 2014 at 13:18

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About structure of parabolic subgroups of finite classical algebraic groups

answered Mar 21, 2014 at 20:32

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Are two distinct Weyl chambers always disjoint?

answered Apr 3, 2014 at 21:03

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On radicals of a lie algebra

answered Nov 20, 2013 at 14:45

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real representation of real semi simple Lie algebra

answered Dec 11, 2013 at 21:53

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closure of a set of k-rational points always defined over k?

answered Dec 13, 2013 at 14:33

3 votes

History of Jordan Canonical Form?

answered Dec 18, 2013 at 21:59

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isogeny and congruence subgroup

answered Nov 30, 2013 at 1:03

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Finding a character of height zero

answered Dec 20, 2013 at 22:58

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Tensor products of two irreducible representations of reductive groups and their inclusions

answered Apr 12, 2014 at 17:46

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Complexity of rational $\mathrm{GL}_{n(r)}$-modules

answered Mar 25, 2014 at 19:42

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conjugacy classes in anisotropic semisimple groups

answered Jan 10, 2014 at 19:04

3 votes

Is there any way to determine the "effeciency" of Jantzen's sum formula?

answered Feb 5, 2014 at 14:02

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semisimple category with finite number of simple objects

answered Feb 6, 2014 at 13:36

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Maximal centralizers in General linear group

answered Feb 6, 2014 at 14:48

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704 Answers

Modular reductions of simple characters

Why are these parabolic subgroups opposed?

Idempotents and Structure of Simple GL(n,p) modules in the describing characteristic

How do I show that a separable isogeny is central?

Representations of $\mathrm{SL}(2)$ in characteristic 2

The action of the center on the extended Dynkin diagram

A natural bijection between the orbit spaces of $p$-nilpotent matrices for varying $p$

quasicrystal and penrose tiling, mathematical introduction

Representation Theory of Lie Groups: Reference Request

Connected components of algebraic groups

Root in positive Weyl chamber

A subgroup of the Weyl group

Reference for embeddings of reflection groups (related to folding ADE Coxeter graphs)?

Computing relative Lie algebra cohomology (as appears in Borel-Weil-Bott theorem)

Hilbert's Finiteness Theorem for connected semisimple Lie groups in Weyl's "Classical Groups"

Dimension of the nilpotent centralizer of a nilpotent matrix

About structure of parabolic subgroups of finite classical algebraic groups

Are two distinct Weyl chambers always disjoint?

On radicals of a lie algebra

real representation of real semi simple Lie algebra

closure of a set of k-rational points always defined over k?

History of Jordan Canonical Form?

isogeny and congruence subgroup

Finding a character of height zero

Tensor products of two irreducible representations of reductive groups and their inclusions

Complexity of rational $\mathrm{GL}_{n(r)}$-modules

conjugacy classes in anisotropic semisimple groups

Is there any way to determine the "effeciency" of Jantzen's sum formula?

semisimple category with finite number of simple objects

Maximal centralizers in General linear group