4 citations · 20 across the 16 of their papers we have counts for
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Existence of integral Hopf orders in twists of group algebras
Juan Cuadra, Ehud Meir
We find a group-theoretical condition under which a twist of a group algebra, in Movshev's way, admits an integral Hopf order. Let be a (large enough) number field with ring of…
Non-existence of integral Hopf orders for twists of several simple groups of Lie type
Giovanna Carnovale, Juan Cuadra, Elisabetta Masut
Let be a prime number and , with if and otherwise. Let be any non-trivial twist for the complex group algebra of ar…
Non-existence of Hopf orders for a twist of the alternating and symmetric groups
Juan Cuadra, Ehud Meir
We prove the non-existence of Hopf orders over number rings for two families of complex semisimple Hopf algebras. They are constructed as Drinfel'd twists of group algebras for the…
Orders of Nikshych's Hopf algebra
Juan Cuadra, Ehud Meir
Let be an odd prime number and a number field having a primitive -th root of unity We prove that Nikshych's non-group theoretical Hopf algebra , which is defin…
On the existence of orders in semisimple Hopf algebras
Juan Cuadra, Ehud Meir
We show that there is a family of complex semisimple Hopf algebras that do not admit a Hopf order over any number ring. They are Drinfel'd twists of certain group algebras. The twi…
On two finiteness conditions for Hopf algebras with nonzero integral
Nicolás Andruskiewitsch, Juan Cuadra, Pavel Etingof
A Hopf algebra is co-Frobenius when it has a nonzero integral. It is proved that the composition length of the indecomposable injective comodules over a co-Frobenius Hopf algebra i…
On the structure of (co-Frobenius) Hopf algebras
Nicolas Andruskiewitsch, Juan Cuadra
We introduce a new filtration on Hopf algebras, the standard filtration, generalizing the coradical filtration. Its zeroth term, called the Hopf coradical, is the subalgebra genera…
A sequence to compute the Brauer group of certain quasi-triangular Hopf algebras
Juan Cuadra, Bojana Femic
A deeper understanding of recent computations of the Brauer group of Hopf algebras is attained by explaining why a direct product decomposition for this group holds and describing…
On the Hopf-Schur group of a field
Eli Aljadeff, Juan Cuadra, Shlomo Gelaki +1
Let k be any field. We consider the Hopf-Schur group of k, defined as the subgroup of the Brauer group of k consisting of classes that may be represented by homomorphic images of H…
Extending lazy 2-cocycles on Hopf algebras and lifting projective representations afforded by them
Juan Cuadra, Florin Panaite
We study some problems related to lazy 2-cocycles, such as: extension of (lazy) 2-cocycles to a Drinfeld double and to a Radford biproduct, Yetter-Drinfeld data obtained from lazy…