Direct sum behavior of lattices over sigma-I rings
نویسندگان
چکیده
منابع مشابه
Direct-sum Decompositions over Local Rings
Let (R,m) be a local ring (commutative and Noetherian). If R is complete (or, more generally, Henselian), one has the Krull-Schmidt uniqueness theorem for direct sums of indecomposable finitely generated R-modules. By passing to the m-adic completion b R, we can get a measure of how badly the Krull-Schmidt theorem can fail for a more general local ring. We assign to each finitely generated R-mo...
متن کاملDirect Sum Cancellation for Modules over One-dimensional Rings
Let R be a one-dimensional Noetherian domain with finite normalization R. In the eighties the second-named author and S. Wiegand developed a mechanism for studying the cancellation problem for finitely generated torsion-free R-modules. The key idea, described in [Wie84] and [WW87], is to represent a given torsion-free module M as a pullback: M −→ RM ↓ ↓ M/fM −→ RM/fM ∗This research was initiate...
متن کاملDirect-sum decompositions over one-dimensional Cohen-Macaulay local rings
1 Alberto Facchini, Dipartimento di Matematica Pura e Applicata, Università di Padova, Via Belzoni 7, I-35131 Padova, Italy, [email protected] 2 Wolfgang Hassler, Institut für Mathematik und Wissenschaftliches Rechnen, Karl-Franzens-Universität Graz, Heinrichstraße 36/IV, A-8010 Graz, Austria, [email protected] 3 Lee Klingler, Department of Mathematical Sciences, Florida Atlanti...
متن کاملThe unit sum number of Baer rings
In this paper we prove that each element of any regular Baer ring is a sum of two units if no factor ring of R is isomorphic to Z_2 and we characterize regular Baer rings with unit sum numbers $omega$ and $infty$. Then as an application, we discuss the unit sum number of some classes of group rings.
متن کاملLattices of Subautomata and Direct Sum Decompositions of Automata
The subject of this paper are general properties of direct sum decompositions of automata. Using certain properties of the lattice Sub(A) of subautomata of an automaton A and its Boolean part, lattices of direct sum congruences and direct sum decompositions of A are characterized. We show that every automaton A can be represented as a direct sum of direct sum indecomposable automata, and that t...
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 Pure and Applied Algebra
سال: 1988
ISSN: 0022-4049
DOI: 10.1016/0022-4049(88)90084-9