Murnaghan-Nakayama rule for the cyclotomic Hecke algebra and applications

Abstract: We derive a Murnaghan-Nakayama rule for irreducible characters of the cyclotomic Hecke algebra on certain standard elements, which fully determine their values. This work builds upon our recent multi-parameter Murnaghan-Nakayama rule for Macdonald polynomials. Our Murnaghan-Nakayama rule can be readily specialized to retrieve various existing rules, including those for the complex reflection group of type $G(m, 1, n)$ and the Iwahori-Hecke algebra in types $A$ and $B$. In a dual picture, we establish an iterative formula for the irreducible characters on upper multipartitions, utilizing the vertex operator realization of Schur functions. As applications we derive an Regev-type formula and an L\"ubeck-Prasad-Adin-Roichman-type formula for the cyclotomic Hecke algebra, thereby extending the corresponding formulas for the Iwahori-Hecke algebra in type $A$ and the complex reflection group of type $G(m,1,n)$ to the setting of the cyclotomic Hecke algebra, respectively. Finally, we introduce the notion of the multiple bitrace of the cyclotomic Hecke algebra to formulate the second orthogonal relation of the irreducible characters. We also provide a general combinatorial rule to compute the multiple bitrace.