Abstract:
We study highest-weight representations of the non-semisimple complex
Lie group $D_{n-1/2}$ used for separating multiple points of the spectrum
in the reduction $D_n\downarrow D_{n-1}$. In particular, we find formulae
for the characters and dimensions of these representations,
which turn out to be similar to the well-known Weyl formulae
for classical Lie groups.
Keywords:semiclassical intermediate Lie groups, finite-dimensional highest-weight representations,
branching rules, weight basis, character and dimension of a representation of a Lie group.