# Strange Expectations and the Winnie-the-Pooh Problem

• Published in 2018
In the collection
Motivated by the study of simultaneous cores, we give three proofs (in varying levels of generality) for the expected norm of a weight in a highest weight representation of a complex simple Lie algebra. First, we argue directly using the polynomial method and the Weyl character formula. Second, we use the combinatorics of semistandard tableaux to obtain the result in type A. Third, and most interestingly, we relate this problem to the "Winnie-the-Pooh problem" regarding orthogonal decompositions of Lie algebras; although this approach offers the most explanatory power, it applies only to Cartan types other than A and C. We conclude with computations of many combinatorial cumulants.

## Other information

key
StrangeExpectationsandtheWinniethePoohProblem
type
article
2022-08-22
date_published
2018-09-14

### BibTeX entry

@article{StrangeExpectationsandtheWinniethePoohProblem,
key = {StrangeExpectationsandtheWinniethePoohProblem},
type = {article},
title = {Strange Expectations and the Winnie-the-Pooh Problem},
author = {Marko Thiel and Nathan Williams},
abstract = {Motivated by the study of simultaneous cores, we give three proofs (in
varying levels of generality) for the expected norm of a weight in a highest
weight representation of a complex simple Lie algebra. First, we argue directly
using the polynomial method and the Weyl character formula. Second, we use the
combinatorics of semistandard tableaux to obtain the result in type A. Third,
and most interestingly, we relate this problem to the "Winnie-the-Pooh problem"
regarding orthogonal decompositions of Lie algebras; although this approach
offers the most explanatory power, it applies only to Cartan types other than A
and C. We conclude with computations of many combinatorial cumulants.},
comment = {},
}