Fock space representation of the circle quantum group

Abstract: In [arXiv:1711.07391] we have defined quantum groups $\mathbf{U}\upsilon(\mathfrak{sl}(\mathbb{R}))$ and $\mathbf{U}\upsilon(\mathfrak{sl}(S^1))$, which can be interpreted as continuous generalizations of the quantum groups of the Kac-Moody Lie algebras of finite, respectively affine type $A$. In the present paper, we define the Fock space representation $\mathcal{F}{\mathbb{R}}$ of the quantum group $\mathbf{U}\upsilon(\mathfrak{sl}(\mathbb{R}))$ as the vector space generated by real pyramids (a continuous generalization of the notion of partition). In addition, by using a variant of the "folding procedure" of Hayashi-Misra-Miwa, we define an action of $\mathbf{U}\upsilon(\mathfrak{sl}(S^1))$ on $\mathcal{F}{\mathbb{R}}$.