منابع مشابه
Seminormal Rings (following
The Traverso-Swan theorem says that a reduced ring A is seminormal if and only if the natural homomorphism PicA→ PicA[X] is an isomorphism ([18, 17]). We give here all the details needed to understand the elementary constructive proof for this result given by Thierry Coquand in [2]. This example is typical of a new constructive method. The final proof is simpler than the initial classical one. ...
متن کاملSeminormal Forms and Gram Determinants for Cellular Algebras
This paper develops an abstract framework for constructing “seminormal forms” for cellular algebras. That is, given a cellular R–algebra A which is equipped with a family of JM–elements we give a general technique for constructing orthogonal bases for A, and for all of its irreducible representations, when the JM–elements separate A. The seminormal forms for A are defined over the field of frac...
متن کاملCastelnuovo-Mumford regularity of seminormal simplicial affine semigroup rings
We show that the Eisenbud-Goto conjecture holds for seminormal simplicial affine semigroup rings. Moreover we prove an upper bound for the Castelnuovo-Mumford regularity in terms of the dimension, which is similar as in the normal case. Finally we compute explicitly the regularity of full Veronese rings.
متن کاملMatroid intersection, pointer chasing, and Young's seminormal representation of Sn
We consider the number of queries needed to solve the matroid intersection problem, a question raised by Welsh (1976). Given two matroids of rank r on n elements, it is known that O(nr) independence queries suffice. However, no non-trivial lower bounds are known for this problem. We make the first progress on this question. We describe a family of instances of rank r = n/2 based on a pointer ch...
متن کاملSeminormal Representations of Weyl Groups and Iwahori – Hecke Algebras
The purpose of this paper is to describe a general procedure for computing analogues of Young’s seminormal representations of the symmetric groups . The method is to generalize the Jucys – Murphy elements in the group algebras of the symmetric groups to arbitrary Weyl groups and Iwahori – Hecke algebras . The combinatorics of these elements allow one to compute irreducible representations expli...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Algebra
سال: 1980
ISSN: 0021-8693
DOI: 10.1016/0021-8693(80)90166-0