We use monoidal category methods to study the noncommutative geometry of nonassociative algebras obtained by a Drinfeld-type cochain twist. These are the so-called quasialgebras and include the octonions as braided-commutative but nonassociative coordinate rings, as well as quasialgebra versions Cq(G) of the standard q-deformation quantum groups. We introduce the notion of ribbon algebras in th...

The determination of cyclic (co)homology of a given algebra is a quite important and difficult problem. Let us briefly recall some of the results obtained that are somehow related to our paper. The cyclic homology of group algebras over fields of characteristic 0 was computed by Burghelea, [3]. For a complete algebraic proof of Burghelea’s result the reader is referred to [19], while a relative...

A standard associative graded algebra R over a field k is called Koszul if k admits a linear resolution as an R-module. A (right) R-module M is called Koszul if it admits a linear resolution too. Here we study a special class of Koszul algebras — roughly say, algebras having a lot of Koszul cyclic modules. Commutative algebras with similar properties (so-called algebras with Koszul filtrations)...

• Vectorspaces over division rings • Matrices, opposite rings • Semi-simple modules and rings • Semi-simple algebras • Reduced trace and norm • Other criteria for simplicity • Involutions • Brauer group of a field • Tensor products of fields • Crossed product construction of simple algebras • Cyclic algebra construction of simple algebras • Quaternion algebras • Examples • Unramified extensions...

in this paper we define s algebras and show that every finite group can be found in some s algebra.  we define and study the s degree of a finite group and determine the s degree of several classes of finite groups such as cyclic groups, elementary abelian $p$-groups, and dihedral groups $d_p$.

We show that two flat differential graded algebras whose derived categories are equivalent by a derived functor have isomorphic cyclic homology. In particular, ‘ordinary’ algebras over a field which are derived equivalent [48] share their cyclic homology, and iterated tilting [19] [3] preserves cyclic homology. This completes results of Rickard’s [48] and Happel’s [18]. It also extends well kno...