User Jim Humphreys

12 votes

0 answers

519 views

Irreducible representations of Weyl group of F$_4$ on zero weight spaces?

asked Nov 7, 2014 at 18:01

12 votes

1 answer

688 views

Comparing a Chevalley basis with the canonical basis of the adjoint module?

asked Feb 3, 2015 at 15:41

12 votes

0 answers

424 views

Reference for class of involutions containing longest element of finite Coxeter group?

asked May 5, 2015 at 23:30

12 votes

0 answers

216 views

Failure of surjectivity in Hotta-Springer specialization: examples for special unipotents?

asked Oct 15, 2015 at 23:02

12 votes

1 answer

1k views

Smallest dimension of nontrivial representation of a simple Lie algebra over `$\mathbb{C}$`

asked Sep 30, 2012 at 13:23

11 votes

4 answers

2k views

Textbook source for finite group properties deducible from character table?

asked May 21, 2012 at 18:45

11 votes

1 answer

1k views

Counting conjugacy classes in simple groups of Lie type

asked Jun 1, 2013 at 14:38

11 votes

2 answers

854 views

Upper bound on order of finite subgroups of GL_n(Z_p)?

asked Apr 20, 2013 at 20:41

11 votes

2 answers

769 views

Finite nonabelian groups with few positive real character values?

asked Feb 22, 2011 at 20:36

11 votes

3 answers

554 views

Uniform setting for computing orders of algebraic groups over finite quotients of the integers?

asked Feb 10, 2012 at 21:25

10 votes

0 answers

881 views

Invariance of Euler characteristic under base change for sheaf cohomology of flag varieties

asked Oct 14, 2010 at 11:58

10 votes

1 answer

1k views

Are there "reasonable" criteria for existence/non-existence of Levi factors or their conjugacy in prime characteristic?

asked Apr 21, 2010 at 21:30

10 votes

1 answer

842 views

Is there a "correct" general setting for the principle: "tensoring any object with a projective object yields another projective"?

asked Sep 7, 2010 at 14:08

9 votes

0 answers

668 views

Role of nontrivial component groups in Springer Correspondence?

asked Mar 14, 2010 at 18:03

9 votes

2 answers

485 views

Reference for restriction of a simple module over a splitting field to a smaller field?

asked Mar 13, 2012 at 23:01

9 votes

1 answer

977 views

Kazhdan-Lusztig graph for the Springer fiber of the minimal special unipotent class?

asked Apr 5, 2011 at 0:56

9 votes

2 answers

1k views

Levi decomposition in disconnected linear algebraic group (characteristic 0)?

asked Jun 9, 2013 at 23:52

9 votes

1 answer

1k views

Optimal definition of "paving by affine spaces"?

asked Nov 11, 2014 at 15:00

9 votes

2 answers

1k views

Examples of Richardson orbit closures not having a symplectic resolution?

asked Jun 12, 2014 at 15:21

9 votes

2 answers

701 views

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

asked Jul 29, 2013 at 13:51

8 votes

0 answers

408 views

Connection between two theorems on character values?

asked Apr 7, 2014 at 15:56

8 votes

2 answers

966 views

Unipotent algebraic group action on quasi-affine (vs. affine) variety?

asked Apr 13, 2017 at 19:16

7 votes

1 answer

614 views

Number of Richardson orbits in simple Lie algebras of types $E_n$?

asked Jun 16, 2014 at 14:37

7 votes

1 answer

912 views

Optimal reference for tensor product of symmetric bilinear forms?

asked May 23, 2011 at 22:43

7 votes

2 answers

301 views

Reference for projective covers of direct products of finite groups?

asked Oct 27, 2011 at 21:51

7 votes

2 answers

780 views

Finite groups with a character having very few nonzero values?

asked May 4, 2010 at 21:30

7 votes

1 answer

476 views

Centralizer of longest element in a finite irreducible Weyl group: related to folding of ADE graphs?

asked Oct 6, 2017 at 0:19

6 votes

1 answer

1k views

Nilpotent matrices related to Lie algebras of special orthogonal groups in characteristic 0

asked Mar 2, 2011 at 23:52

6 votes

3 answers

555 views

Source for embedding multiplicative group of an algebraic closure of a finite field?

asked Apr 25, 2012 at 16:04

6 votes

2 answers

856 views

Algorithm for Brauer lifting via Brauer tree?

asked May 9, 2012 at 19:28

Stack Exchange Network

74 Questions

Irreducible representations of Weyl group of F$_4$ on zero weight spaces?

Comparing a Chevalley basis with the canonical basis of the adjoint module?

Reference for class of involutions containing longest element of finite Coxeter group?

Failure of surjectivity in Hotta-Springer specialization: examples for special unipotents?

Smallest dimension of nontrivial representation of a simple Lie algebra over `$\mathbb{C}$`

Textbook source for finite group properties deducible from character table?

Counting conjugacy classes in simple groups of Lie type

Upper bound on order of finite subgroups of GL_n(Z_p)?

Finite nonabelian groups with few positive real character values?

Uniform setting for computing orders of algebraic groups over finite quotients of the integers?

Invariance of Euler characteristic under base change for sheaf cohomology of flag varieties

Are there "reasonable" criteria for existence/non-existence of Levi factors or their conjugacy in prime characteristic?

Is there a "correct" general setting for the principle: "tensoring any object with a projective object yields another projective"?

Role of nontrivial component groups in Springer Correspondence?

Reference for restriction of a simple module over a splitting field to a smaller field?

Kazhdan-Lusztig graph for the Springer fiber of the minimal special unipotent class?

Levi decomposition in disconnected linear algebraic group (characteristic 0)?

Optimal definition of "paving by affine spaces"?

Examples of Richardson orbit closures not having a symplectic resolution?

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

Connection between two theorems on character values?

Unipotent algebraic group action on quasi-affine (vs. affine) variety?

Number of Richardson orbits in simple Lie algebras of types $E_n$?

Optimal reference for tensor product of symmetric bilinear forms?

Reference for projective covers of direct products of finite groups?

Finite groups with a character having very few nonzero values?

Centralizer of longest element in a finite irreducible Weyl group: related to folding of ADE graphs?

Nilpotent matrices related to Lie algebras of special orthogonal groups in characteristic 0

Source for embedding multiplicative group of an algebraic closure of a finite field?

Algorithm for Brauer lifting via Brauer tree?