4 papers · 1 filter
A non-semisimple Kitaev lattice model
Sebastian Halbig, Ulrich Krähmer
The construction of the topologically protected code space of Kitaev's model for fault-tolerant quantum computation is extended from complex semisimple to arbitrary finite-dimensio…
The ring of differential operators on a monomial curve is a Hopf algebroid
Ulrich Krähmer, Myriam Mahaman
This article considers cuspidal curves whose coordinate rings are numerical semigroup algebras. Using a general result about descent of Hopf algebroid structures, their rings of di…
A remark on the Hochschild dimension of liberated quantum groups
Tomasz Brzeziński, Ulrich Krähmer, Réamonn Ó Buachalla +1
Let be a Hopf algebra equipped with a projection onto the coordinate Hopf algebra of a semisimple algebraic group . It is shown that if admits a suitabl…
Pointed Hopf algebra (co)actions on rational functions
Ulrich Krähmer, Blessing Bisola Oni
This article studies the construction of Hopf algebras acting on a given algebra in terms of algebra morphisms . The approach is par…