17 citations · 56 across the 19 of their papers we have counts for
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Twisted Dirac operator on quantum SU(2) in disc coordinates
Ulrich Kraehmer, Elmar Wagner
The quantum disc is used to define a noncommutative analogue of a dense coordinate chart and of left-invariant vector fields on quantum SU(2). This yields two twisted Dirac operato…
A Hopf algebra without modular pair in involution
Sebastian Halbig, Ulrich Kraehmer
The aim of this short note is to communicate an example of a finite-dimensional Hopf algebra that does not admit a modular pair in involution in the sense of Connes and Moscovici.
The nodal cubic and quantum groups at roots of unity
Ulrich Kraehmer, Manuel Martins
In a recent article, the coordinate ring of the nodal cubic was given the structure of a quantum homogeneous space. Here the corresponding coalgebra Galois extension is expressed i…
(Weak) incidence bialgebras of monoidal categories
Ulrich Kraehmer, Lucia Rotheray
Incidence coalgebras of categories in the sense of Joni and Rota are studied, specifically cases where a monoidal product on the category turns these into (weak) bialgebras. The ov…
Cyclic homology arising from adjunctions
Niels Kowalzig, Ulrich Kraehmer, Paul Slevin
Given a monad and a comonad, one obtains a distributive law between them from lifts of one through an adjunction for the other. In particular, this yields for any bialgebroid the Y…
On the Dolbeault--Dirac Operator of Quantized Symmetric Spaces
Ulrich Kraehmer, Matthew Tucker-Simmons
The Dolbeault complex of a quantized compact Hermitian symmetric space is expressed in terms of the Koszul complex of a braided symmetric algebra of Berenstein and Zwicknagl. This…