On multiplicity-free skew characters and the Schubert Calculus

In this paper we classify the multiplicity-free skew characters of the symmetric group. Furthermore we show that the Schubert calculus is equivalent to that of skew characters in the following sense: If we decompose the product of two Schubert classes we get the same as if we decompose a skew character and replace the irreducible characters by Schubert classes of the `inverse' partitions (Theorem 4.2).Comment: 14 pages, to appear in Annals. Comb. minor changes from v1 to v2 as suggested by the referees, Example 3.4 inserted so numeration changed in section

Zassenhaus conjecture for central extensions of S5

We confirm a conjecture of Zassenhaus about rational conjugacy of torsion units in integral group rings for a covering group of the symmetric group S5 and for the general linear group GLð2; 5Þ. The first result, together with others from the literature, settles the conjugacy question for units of prime-power order in the integral group ring of a finite Frobenius group

Open Problems on Central Simple Algebras

We provide a survey of past research and a list of open problems regarding central simple algebras and the Brauer group over a field, intended both for experts and for beginners.Comment: v2 has some small revisions to the text. Some items are re-numbered, compared to v

Representations of the Covering Groups of the Symmetric Groups and Their Combinatorics

and their combinatoric

On Kronecker Products Of Complex Representations Of The Symmetric And Alternating Groups

this paper we study the homogeneous tensor product

ON KRONECKER PRODUCTS OF CHARACTERS OF THE SYMMETRIC GROUPS WITH FEW COMPONENTS

Abstract. Confirming a conjecture made by Bessenrodt and Kleshchev in 1999, we classify all Kronecker products of characters of the symmetric groups with only three or four components. On the way towards this result, we obtain new information about constituents in Kronecker products. 1