La K-théorie stable
Using a notion of distance between indecomposable modules we deduce new characterizations of laura algebras and quasi-directed Auslander-Reiten components. Afterwards, we investigate the infinite radical of Artin algebras and show that there exist infinitely many non-directing modules between two indecomposable modules X and Y if . We draw as inference that a convex component is quasi-directed if and only if it is almost directed.
We introduce the notion of a lazy 2-cocycle over a monoidal Hom-Hopf algebra and determine all lazy 2-cocycles for a class of monoidal Hom-Hopf algebras. We also study the extension of lazy 2-cocycles to a Radford Hom-biproduct.
Les foncteurs entre espaces vectoriels, ou représentations génériques des groupes linéaires d’après Kuhn, interviennent en topologie algébrique et en -théorie comme en théorie des représentations. Nous présentons ici une nouvelle méthode pour aborder les problèmes de finitude et la dimension de Krull dans ce contexte.Plus précisément, nous démontrons que, dans la catégorie des foncteurs entre espaces vectoriels sur , le produit tensoriel entre , où désigne le foncteur projectif , et un foncteur...
Soit un anneau principal et un -module de torsion de type fini. Nous donnons une preuve élémentaire du fait que tout automorphisme de -algèbre de est intérieur.
A ring is called a left APP-ring if the left annihilator is right -unital as an ideal of for any element . We consider left APP-property of the skew formal power series ring where is a ring automorphism of . It is shown that if is a ring satisfying descending chain condition on right annihilators then is left APP if and only if for any sequence of elements of the ideal
Let be the polynomial ring over a ring with unity. A polynomial is referred to as a left annihilating content polynomial (left ACP) if there exist an element and a polynomial such that and is not a right zero-divisor polynomial in . A ring is referred to as left EM if each polynomial is a left ACP. We observe the structure of left EM rings with various properties, and study the relationships between the one-sided EM condition and other standard ring theoretic conditions. Moreover,...
We define a notion of left section in an Auslander-Reiten component, by weakening one of the axioms for sections. We derive a generalisation of the Liu-Skowroński criterion for tilted algebras, then apply our results to describe the Auslander-Reiten components lying in the left part of an artin algebra.