Irreducible modules over the universal central extension of the planar Galilean conformal algebra

Abstract

In this paper, we study the representation theory of the universal central extension $\mathcal{G}$ of the infinite-dimensional Galilean conformal algebra, introduced by Bagchi-Gopakumar, in $(2+1)$ dimensional space-time, which was named the planar Galilean conformal algebra by Aizawa. More precisely, we construct a family of Whittaker modules $W_{{\psi }_{m,n}}$ over $\mathcal{G}$ while the necessary and sufficient conditions for these modules to be irreducible are given when $m\in {\mathbb{Z}}_{+},n\in \mathbb{N}$ and $m,n$ have the same parity. Moreover, the irreducible criteria of the tensor product modules $\Omega (\lambda ,\eta ,\sigma ,0)\otimes R,\Omega (\lambda ,\eta ,0,\sigma )\otimes R$ over $\mathcal{G}$ are obtained, where $\Omega (\lambda ,\eta ,\sigma ,0),\Omega (\lambda ,\eta ,0,\sigma )$ are $\mathcal{U}(\mathfrak{h})$-free modules of rank one over $\mathcal{G}$ and $R$ is an irreducible restricted module over $\mathcal{G}$. Also, the isomorphism classes of these tensor product modules are determined.

24 pages