Positive combinatorial formulas for Kostka–Foulkes polynomials beyond type A

Derive positive combinatorial formulas for Kostka–Foulkes polynomials, or q-analogues of weight multiplicities, for Lie types beyond type A_{n-1}.

Background

The paper explains that atomic decompositions of crystals are relevant to computing positive combinatorial formulas for Kostka–Foulkes polynomials. While such formulas are discussed in the context of type A_{n-1}, the corresponding problem beyond type A_{n-1} is identified as unresolved. This provides motivation for studying atomic decompositions and crystal embeddings as tools that may eventually extend positive formulas to other Lie types.

References

Atomic decompositions of crystals arise in the computation of positive combinatorial formulas for Kostka--Foulkes polynomials, or $q$-analogues of weight multiplicities, which beyond type $A_{n-1}$ remains an open problem.

Unveiling Crystal Embeddings: New Perspectives on String Polytopes and Atomic Decompositions  (2505.22127 - Bossinger et al., 28 May 2025) in Section 1, Introduction