36 citations · 126 across the 26 of their papers we have counts for
30 papers
Central extensions for loop groups of area-preserving diffeomorphisms and their fuzzy sphere limits
Bas Janssens, Zhenghan Wang
We classify central extensions for the loop group LSDiff(S^2) of area-preserving diffeomorphisms of the 2-sphere, and of related twisted loop groups. We then show that the correspo…
Local noncommutative De Leeuw Theorems beyond reductive Lie groups
Bas Janssens, Benjamin Oudejans
Let be a discrete subgroup of a unimodular locally compact group . In Math. Ann. 388, 4251-4305 (2024), it was shown that the norm of a Fourier multiplier on c…
Universal central extension of the Lie algebra of exact divergence-free vector fields
Bas Janssens, Leonid Ryvkin, Cornelia Vizman
We construct the universal central extension of the Lie algebra of exact divergence-free vector fields, proving a conjecture by Claude Roger from 1995. The proof relies on the anal…
Generalized Positive Energy Representations of the Group of Compactly Supported Diffeomorphisms
Bas Janssens, Milan Niestijl
Motivated by asymptotic symmetry groups in general relativity, we consider projective unitary representations of the Lie group of compactly suppor…
How an action that stabilizes a bundle gerbe gives rise to a Lie group extension
Bas Janssens, Peter Kristel
Let be a bundle gerbe with connection on a smooth manifold , and let be a smooth action of a Fréchet--Lie group on $M…
Local and multilinear noncommutative de Leeuw theorems
Martijn Caspers, Bas Janssens, Amudhan Krishnaswamy-Usha +1
Let be a discrete subgroup of a locally compact unimodular group . Let be a -multiplier on with and let $T_{m}: L_p(\widehat{G})…