Drinfeld recently suggested to replace projective modules by the flat Mittag-Leffler ones in
the definition of an infinite dimensional vector bundle on a scheme X (Drinfeld, 2006 [8]) …

Let $(G, X) $ be a PEL-Shimura datum of type AC in Kottwitz's classification. Assume $ G_
{\mathbf {Q} _p} $ is unramified. We show that the good reduction locus of the infinite $ p …

This paper investigates the structure of cyclically pure (or C-pure) projective modules. In
particular, it is shown that a ring R is left Noetherian if and only if every C-pure projective left …

An error in Corollary 9.32 of [C. Faith, Rings and Things and a Fine Array of Twentieth
Century Associative Algebra, Mathematical Surveys and Monographs, Vol. 65 (American …

We study the class of rings in which every P-flat module is flat. In domains this property
characterizes Prüfer domains. We investigate the preservation of this property under …

Let R be a commutative ring with a nonzero identity and M an R-module. Set ϕ-tor (M)={x∈
M| sx= 0 for some s∈ R∖ Nil (R)}, if ϕ-tor (M)= M then M is called a ϕ-torsion module. An R …

In a recent paper of Holston, López-Permouth, Mastromatteo and Simental-Rodriguez, a ring
R is defined to have no subprojective middle class if the subprojectivity domain of any R …

In this paper, we study the class of rings in which every flat ideal is projective. We investigate
the stability of this property under homomorphic image, and its transfer to various contexts of …

This paper studies the class of rings in which every finitely projective ideal is projective (FPP-
ring for short). We examine the transfer of this property to various context of commutative ring …

Let $ R $ be a ring. A morphism $\alpha: X\rightarrow Y $ of left $ R $-modules is called a
finitely phantom morphism if for each morphism ${\beta: F\rightarrow X} $ with $ F $ finitely …