Dimension homologique de modules simples
Dimension in algebraic frames, II: Applications to frames of ideals in
This paper continues the investigation into Krull-style dimensions in algebraic frames. Let be an algebraic frame. is the supremum of the lengths of sequences of (proper) prime elements of . Recently, Th. Coquand, H. Lombardi and M.-F. Roy have formulated a characterization which describes the dimension of in terms of the dimensions of certain boundary quotients of . This paper gives a purely frame-theoretic proof of this result, at once generalizing it to frames which are not necessarily...
Dimension injective des produits croisés.
Dimensions globales des extensions de Ore et des algèbres de Weyl
Ding projective and Ding injective modules over trivial ring extensions
Let be a trivial extension of a ring by an --bimodule such that , , and have finite flat dimensions. We prove that is a Ding projective left -module if and only if the sequence is exact and is a Ding projective left -module. Analogously, we explicitly describe Ding injective -modules. As applications, we characterize Ding projective and Ding injective modules over Morita context rings with zero bimodule homomorphisms.
Diophantische Gleichungen und die universelle Eigenschaft Finslerscher Zahlen.
Direct decompositions and basic subgroups in commutative group rings
An attractive interplay between the direct decompositions and the explicit form of basic subgroups in group rings of abelian groups over a commutative unitary ring are established. In particular, as a consequence, we give a simpler confirmation of a more general version of our recent result in this aspect published in Czechoslovak Math. J. (2006).
Direct finiteness of group rings - a simple proof of the Kaplansky's conjecture for finite groups
Direct image of the de Rham system associated with a rational double point
Direct products of linearly compact primary rings
Direct sums of -rings and radical rings.
Direct sums of semi-projective modules
We investigate when the direct sum of semi-projective modules is semi-projective. It is proved that if R is a right Ore domain with right quotient division ring Q ≠ R and X is a free right R-module then the right R-module Q ⊕ X is semi-projective if and only if there does not exist an R-epimorphism from X to Q.
Directing components for quasitilted algebras
We show here that a directing component of the Auslander-Reiten quiver of a quasitilted algebra is either postprojective or preinjective or a connecting component.
Directoids with an antitone involution
We investigate -directoids which are bounded and equipped by a unary operation which is an antitone involution. Hence, a new operation can be introduced via De Morgan laws. Basic properties of these algebras are established. On every such an algebra a ring-like structure can be derived whose axioms are similar to that of a generalized boolean quasiring. We introduce a concept of symmetrical difference and prove its basic properties. Finally, we study conditions of direct decomposability of directoids...
Discrete Analogues of the Heisenberg-Weyl Algebra.
Discrete minimal surface algebras.
Diskriminanten und Picard-Invarianten freier quadratischer Erweiterungen.
Distinguishing derived equivalence classes using the second Hochschild cohomology group
We study the second Hochschild cohomology group of the preprojective algebra of type D₄ over an algebraically closed field K of characteristic 2. We also calculate the second Hochschild cohomology group of a non-standard algebra which arises as a socle deformation of this preprojective algebra and so show that the two algebras are not derived equivalent. This answers a question raised by Holm and Skowroński.
Distributive lattices of t-k-Archimedean semirings
A semiring S in 𝕊𝕃⁺ is a t-k-Archimedean semiring if for all a,b ∈ S, b ∈ √(Sa) ∩ √(aS). Here we introduce the t-k-Archimedean semirings and characterize the semirings which are distributive lattice (chain) of t-k-Archimedean semirings. A semiring S is a distributive lattice of t-k-Archimedean semirings if and only if √B is a k-ideal, and S is a chain of t-k-Archimedean semirings if and only if √B is a completely prime k-ideal, for every k-bi-ideal B of S.
Distributively generated near-rings with descending chain condition.