M. Caspers

collaborators

2 papers

math.OA2016

Weight theory for ultraproducts

Martijn Caspers

For a family of von Neumann algebras $M_{j}$ equipped with normal weights $φ_{j}$ we define the ultraproduct weight $(φ_{j})_{ω}$ on the Groh--Raynaud ultrapower $\prod_{j, ω} \m…

math.OA2015

Weak type commutator and Lipschitz estimates: resolution of the Nazarov-Peller conjecture

Martijn Caspers, Denis Potapov, Fedor Sukochev +1

Let $M$ be a semi-finite von Neumann algebra and let $f : R \to C$ be a Lipschitz function. If $A, B \in M$ are self-adjoint operators suc…