We study a class of infinite dimensional Lie algebras called generalized Witt algebras (in one variable). These include the classical Witt algebra and the centerless Virasoro algebra as importantâ€¦ (More)

Introduction. One of the first things we learn in abstract algebra is the notion of a cyclic group. For every positive integer n, we have Zn, the group of integers modulo n. When n is prime, a simpleâ€¦ (More)

Let Fn = ã€ˆx1, . . . , xnã€‰ denote the free group with generators {x1, . . . , xn} . Nielsen and Magnus described generators for the kernel of the canonical epimorphism from the automorphism group ofâ€¦ (More)

In this paper we will study the cohomology of a family of p-groups associated to Fp-Lie algebras. More precisely we study a category BGrp of p-groups which will be equivalent to the category ofâ€¦ (More)

In this paper we find upper bounds for the nilpotency degree of some ideals in the cohomology ring of a finite group by studying fixed point free actions of the group on suitable spaces. The idealsâ€¦ (More)

In this paper we study various simplicial complexes associated to the commutative structure of a finite groupG. We defineNC(G) (resp. C(G)) as the complex associated to the poset of pairwiseâ€¦ (More)

We will provide an example of a p-group G which has elements of order p in some of its integral cohomology groups but which also has the property that p annihilates HÌ„(G; Z) for all sufficiently highâ€¦ (More)

Let E be a central extension of the form 0 â†’ V â†’ G â†’ W â†’ 0 where V and W are elementary abelian 2-groups. Associated to E there is a quadratic map Q : W â†’ V , given by the 2-power map, which uniquelyâ€¦ (More)

In this paper we provide calculations for the mod p cohomology of certain pâ€“groups, using topological methods. More precisely, we look at p-groups G defined as central extensions 1 â†’ V â†’ G â†’ W â†’ 1 ofâ€¦ (More)