math.FA — Functional Analysis
A bridge between analysis on local fields and quantum groups: the noncompact case
Let be a non-Archimedean local field with residue cardinality and let . We establish a radial correspondence between analysis on and Woronowicz's quantum group , with . For every , the radial Taibleson operator of order is unitarily equivalent, through a unitary commuting with dilations, to a bilateral birth–death operator with Hahn–Exton -Bessel eigenfunctions. Their Dirichlet forms are equivalent on the same weighted sequence space, with optimal comparison constants. For , the bilateral operator is the radial part of a self-adjoint Casimir on the quantum plane , whose heat semigroup is covariant and completely positive. We further obtain these quantum-plane dynamics by contraction of the compact Casimir dynamics on the Podleś sphere, with Mosco convergence of the forms and pointwise norm convergence of the compressed heat maps.