Almost Cohen-Macaulay and almost regular algebras via almost flat extensions
نویسندگان
چکیده
منابع مشابه
RESULTS ON ALMOST COHEN-MACAULAY MODULES
Let $(R,underline{m})$ be a commutative Noetherian local ring and $M$ be a non-zero finitely generated $R$-module. We show that if $R$ is almost Cohen-Macaulay and $M$ is perfect with finite projective dimension, then $M$ is an almost Cohen-Macaulay module. Also, we give some necessary and sufficient condition on $M$ to be an almost Cohen-Macaulay module, by using $Ext$ functors.
متن کاملCombinatorial Decompositions of Rings and Almost Cohen-Macaulay Complexes
The concept of a combinatorial decomposition of a graded K algebra was introduced by Baclawski-Garsia [4], and they showed that every (finitelygenerated) graded K algebra has such a decomposition. The purpose of this paper is to prove some general properties of combinatorial decompositions, which are useful for finding such decompositions. We then show how to compute combinatorial decomposition...
متن کاملAlmost Flat Manifolds
1.1. We denote by V a connected ^-dimensional complete Riemannian manifold, by d = d(V) the diameter of V, and by c = c(V) and c~ = c~(V), respectively, the upper and lower bounds of the sectional curvature of V. We set c = c(V) = max (| c1, | c~ |). We say that F i s ε-flat, ε > 0, if cd < ε. 1.2. Examples. a. Every compact flat manifold is ε-flat for any ε > 0. b. Every compact nil-manifold p...
متن کاملAlmost n-Multiplicative Maps between Frechet Algebras
For the Fr'{e}chet algebras $(A, (p_k))$ and $(B, (q_k))$ and $n in mathbb{N}$, $ngeq 2$, a linear map $T:A rightarrow B$ is called textit{almost $n$-multiplicative}, with respect to $(p_k)$ and $(q_k)$, if there exists $varepsilongeq 0$ such that$$q_k(Ta_1a_2cdots a_n-Ta_1Ta_2cdots Ta_n)leq varepsilon p_k(a_1) p_k(a_2)cdots p_k(a_n),$$for each $kin mathbb{N}$ and $a_1, a_2, ldots, a_nin A$. Th...
متن کاملAlmost Free Algebras
In this paper we adopt the terminology of universal algebra. So by a free algebra we will mean that a variety (i.e., an equationally defined class of algebras) is given and the algebra is free in that variety. We will also assume that the language of any variety is countable. In this paper the investigation of the almost free algebras is continued. An algebra is said to be almost free if “most”...
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 Commutative Algebra
سال: 2012
ISSN: 1939-2346
DOI: 10.1216/jca-2012-4-4-445