Cluster ensembles, quantization and the dilogarithm II: The intertwiner
V. V. Fock, A. B. Goncharov
TL;DR
The paper addresses the problem of quantizing cluster ${\cal X}$-varieties and constructing a canonical representation by developing intertwiners built from the quantum dilogarithm. The authors formulate a $\ast$-quantization framework via a Heisenberg algebra ${\cal H}^{\hbar}_{\bf i}$ and a mutation map $\kappa^{\hbar}(\mu_k)$, leveraging the quantum logarithm $\phi^{\hbar}$ and the modular double to connect seed variants and Langlands duals. The main contributions include an explicit intertwiner ${\bf K}_{\mathbf i\to\mathbf i'}$ realizing the mutation between seeds, a bimodule structure on functions on the $\cal A$-space, and a canonical projective representation of the cluster modular groupoid on $L^2({\cal A}^+)$, all grounded in the properties of the quantum dilogarithm $\Phi^{\hbar}$ and quantum logarithm $\phi^{\hbar}$. This framework advances a robust, representation-theoretic approach to quantum cluster varieties with potential applications in quantum geometry and related areas of mathematical physics.
Abstract
The main result is a construction, via the quantum dilogarithm, of certain intertwiner operators, which play the crucial role in the quantization of the cluster X-varieties and construction of the corresponding canonical representation.
