In this paper it is proved that the ''exponent reduction property'' holds for all projective Schur algebras. This was proved in an earlier paper of the authors for a special class, the ''radical abelian algebras.'' The precise statement is as follows: let Ε½ . A be a projective Schur algebra over a f
Exponent Reduction for Radical Abelian Algebras
β Scribed by Eli Aljadeff; Jack Sonn
- Publisher
- Elsevier Science
- Year
- 2000
- Tongue
- English
- Weight
- 83 KB
- Volume
- 223
- Category
- Article
- ISSN
- 0021-8693
No coin nor oath required. For personal study only.
β¦ Synopsis
Let k be a field. A radical abelian algebra over k is a crossed product K/k Ξ± , where K = k T is a radical abelian extension of k, T is a subgroup of K * which is finite modulo k * , and Ξ± β H 2 G K * is represented by a cocycle with values in T . The main result is that if A is a radical abelian algebra over k, and m = exp A β k k Β΅ , where Β΅ denotes the group of all roots of unity, then k contains the mth roots of unity. Applications are given to projective Schur division algebras and projective Schur algebras of nilpotent type.
π SIMILAR VOLUMES
We generalize the definition of the operators corresponding to particle addition in the abelian sandpile models to include a phase factor e ~', where n is the number of topplings in the avalanche, and β’ is a real parameter. The new operators so defined are still abelian, and their derivatives with r
2 Γ 2 . If H is abelian of order 8, we may use K = k H \* , and if H is abelian of order 4 we use K = kD 8 \* . If H βΌ = D 8 , then in the two possible examples, one has K = kD 8 \* and the other has K = kQ 8 \* . If H βΌ = 2 Γ 2 Γ 2 then H has two simple degree 2 characters, Ο 1 and Ο 2 , and they