2025/11/04 by Hytönen, Tuomas, Wu, Lin
Mathematics · #Advanced Harmonic Analysis Research #Classical Analysis and ODEs (math.CA) #FOS: Mathematics #Functional Analysis (math.FA) #Holomorphic and Operator Theory #Nonlinear Partial Differential Equations
paper · doi:10.48550/arxiv.2511.02686
openalex publication_date 2025/11/04 · openalex created_date 2025/11/06 · openalex updated_date 2026/07/28
Extending classical results of Janson and Peetre (1988) on the Schatten class Sp membership of commutators of Riesz potentials on the Euclidean space, we obtain analogous results for commutators [b,T], where T∈\Tε,\widetilde Tα\ belongs to either one of two natural classes of fractional integral operators on a space of homogeneous type. Our approach is based on recent related work of Hytönen and Korte on singular (instead of fractional) integrals; working directly with the kernels, it differs from the Fourier analytic considerations of Janson and Peetre, covering new operators even when specialised to \mathbb Rd. The cleanest case of our characterization in spaces of lower dimension d> 2 and satisfying a (1,2)-Poincaré inequality is as follows. For a parameter ε ∈ (0,(1)/(2)-(1)/(d)) describing the order of the fractional integral Tε , we have a dichotomy: If (d)/(1+dε )