Jim Humphreys
Reputation
35,178
330/400 score
4 74 156
Impact
~644k people reached

 53 Motivating the Casimir element 35 Books you would like to read (if somebody would just write them…) 32 Fields of mathematics that were dormant for a long time until someone revitalized them 28 Rep Theory Consequences of Bott--Weil--Borel 28 What is significant about the half-sum of positive roots?

### Reputation (35,178)

 +10 On Category O in positive characteristic +15 Vanishing of power of nilpotent operator $\mathrm{ad} \, \;e$ in different characteritics +10 Decomposing tensor products of irreducible representations of reductive groups over a finite field +10 “Resume de cours” by J. Tits

### Questions (67)

 49 What are “classical groups”? 42 Origin of terms “flag”, “flag manifold”, “flag variety”? 38 Is Galois theory necessary (in a basic graduate algebra course)? 34 Implications of non-negativity of coefficients of arbitrary Kazhdan-Lusztig polynomials? 32 What role does the “dual Coxeter number” play in Lie theory (and should it be called the “Kac number”)?

### Tags (180)

 1k rt.representation-theory × 305 480 reference-request × 126 750 algebraic-groups × 196 330 ag.algebraic-geometry × 106 729 lie-algebras × 166 228 finite-groups × 68 579 gr.group-theory × 158 120 nt.number-theory × 17 522 lie-groups × 119 100 ho.history-overview × 24

### Account (1)

 MathOverflow 35,178 rep 474156
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