10 citations · 10 across the 11 of their papers we have counts for
14 papers
Graded relations on crossed products
Ofir Schnabel
We classify crossed product gradings for arbitrary groups and fields up to several equivalence relations in terms of group actions and their orbits.
Quotient gradings and the intrinsic fundamental group
Yuval Ginosar, Ofir Schnabel
Quotient grading classes are essential participants in the computation of the intrinsic fundamental group of an algebra . In order to study quotient gradings of a finit…
Units of twisted group rings and their correlations to classical group rings
Geoffrey Janssens, Eric Jespers, Ofir Schnabel
This paper is centered around the classical problem of extracting properties of a finite group from the ring isomorphism class of its integral group ring . This p…
The twisted group ring isomorphism problem over fields
L. Margolis, O. Schnabel
Similarly to how the classical group ring isomorphism problem asks, for a commutative ring , which information about a finite group is encoded in the group ring , the tw…
Categories and weak equivalences of graded algebras
Alexey Gordienko, Ofir Schnabel
When one studies the structure (e.g. graded ideals, graded subspaces, radicals, ...) or graded polynomial identities of graded algebras, the grading group itself does not play an i…
The Herzog-Schönheim Conjecture for small groups and harmonic subgroups
Leo Margolis, Ofir Schnabel
We prove that the Herzog-Schönheim Conjecture holds for any group of order smaller than . In other words we show that in any non-trivial coset partition $\{g_i U_i\}_{i=1…
A different approach to the Fraenkel Conjecture for low values
Ofir Schnabel, Jamie Simpson
We present a new approach to deal with Fraenkel's conjecture, which describes how the integers can be partitioned into sets of rational Beatty sequences, in the case where the nume…
On weak equivalences of gradings
Alexey Gordienko, Ofir Schnabel
When one studies the structure (e.g. graded ideals, graded subspaces, radicals, ...) or graded polynomial identities of graded algebras, the grading group itself does not play an i…
Twisted group ring isomorphism problem
Leo Margolis, Ofir Schnabel
We propose and study a variation of the classical isomorphism problem for group rings in the context of projective representations. We formulate several weaker conditions following…
Groups of central type, maximal Connected Gradings and Intrinsic Fundamental Groups of Complex Semisimple Algebras
Yuval Ginosar, Ofir Schnabel
Maximal connected grading classes of a finite-dimensional algebra are in one-to-one correspondence with Galois covering classes of which admit no proper Galois covering and…
Classification of groups of central type of order
Ofir Schnabel
The classification of abelian groups of central type is well known. However, the description of non-abelian groups of central type which are known to be solvable, is far from being…
Simple twisted group algebras of dimension and their semi-centers
Ofir Schnabel
For simple twisted group algebra over a group , if is Hall subgroup of then the semi-center is simple. Simple twisted groups algebras correspond to groups of…
On the reducibility of exact covering systems
Ofir Schnabel
There exist irreducible exact covering systems (ECS). These are ECS which are not a proper split of a coarser ECS. However, an ECS admiting a maximal modulus which is divisible by…
A graph-theoretic approach for comparing dimensions of components in simply-graded algebras
Yuval Ginosar, Ofir Schnabel
Any simple group-grading of a finite dimensional complex algebra induces a natural family of digraphs. We prove that for a…