Bulg. J. Phys. vol.33 no.s2 (2006), pp. 251-268



Composite Supersymmetric S-functions and Characters of gl(m|n) Representations

E.M.Moens, J.VanderJeugt
DepartmentofAppliedMathematicsandComputerScience,GhentUniversity, Krijgslaan281-S9,B-9000Gent,Belgium
Abstract. It is shown how to associate to a highest weight Λ of the Lie superalgebra gl(m|n) a composite partition ‾ν;μ with composite Young diagram F(‾ν;μ). The corresponding supersymmetric Schur function s‾ν;μ(x/y) is defined. However, it is known that this S-function does not always coincide with the character of the irreducible representation V Λ with highest weight Λ. Only for covariant, contravariant and typical representations the character and the S-function are known to coincide.
Here, the notions of critical composite partitions and critical highest weights are considered. It is shown that for critical composite partitions (subject to a technical restriction) the corresponding gl(m|n) representation VΛ is tame, so its character can be computed. Also for this class of representations the character coincides with the composite supersymmetric S-function s‾ν;μ(x/y). This extends considerably the classes of gl(m|n) representations for which the character can be computed by means of S-functions.

Full-text: PDF

go back