collaborators

6 papers

math.FA2026

Schatten properties of commutators on metric spaces

Tuomas Hytönen

We characterise the Schatten class properties of commutators of singular integrals and pointwise multipliers in a general framework of (quasi-)metric measure spaces.…

math.FA2026

-invariance of oscillatory norms, and Schatten characterisations of commutators

Tuomas Hytönen

Schatten class properties of commutators of pointwise multipliers and singular integral operators have been characterised in a variety of settings. An abstract fram…

math.FA2026

Real-variable theory of function spaces with operator-valued weights in Banach spaces

Tuomas P. Hytönen, Yinqin Li, Dachun Yang +1

While the theory of matrix-weighted function spaces is well established, the majority of previous results in the infinite-dimensional operator-valued setting deal with "no go" theo…

math.FA2026

Real-variable theory of matrix-weighted multi-parameter Besov--Triebel--Lizorkin-type spaces

Fan Bu, Yiqun Chen, Tuomas Hytönen +2

We develop a comprehensive theory for a general class of multi-parameter function spaces of Besov-Triebel-Lizorkin type, with a matrix weight. We prove the equivalence of different…

math.FA2026

Characterisations of Sobolev spaces and constant functions over metric spaces

Tuomas Hytönen, Riikka Korte

In a doubling metric measure space supporting a Poincaré inequality, we give a new characterisation of first-order Sobolev spaces by mean oscillations, and extend prev…

math.FA2025

Schatten properties of commutators of fractional integrals on spaces of homogeneous type

Tuomas Hytönen, Lin Wu

Extending classical results of Janson and Peetre (1988) on the Schatten class membership of commutators of Riesz potentials on the Euclidean space, we obtain analogous result…