Centres and Fixed-Point Rings of Artinian Rings.
Let be a commutative ring with unit. We give some criterions for determining when a direct sum of two CF-modules over is a CF-module. When is local, we characterize the CF-modules over whose tensor product is a CF-module.
Let be a smooth manifold, a local algebra in sense of André Weil, the manifold of near points on of kind and the module of vector fields on . We give a new definition of vector fields on and we show that is a Lie algebra over . We study the cohomology of -differential forms. Résumé. On considère une variété différentielle, une algèbre locale au sens d’André Weil, la variété des points proches de d’espèce et le module des champs de vecteurs sur . On donne une nouvelle...
The notion of the characteristic of rings and its basic properties are formalized [14], [39], [20]. Classification of prime fields in terms of isomorphisms with appropriate fields (ℚ or ℤ/p) are presented. To facilitate reasonings within the field of rational numbers, values of numerators and denominators of basic operations over rationals are computed.
We give Lambek-Carlitz type characterization for completely multiplicative reduced incidence functions in Möbius categories of full binomial type. The -analog of the Lambek-Carlitz type characterization of exponential series is also established.
Let be a commutative ring and a semidualizing -module. We investigate the relations between -flat modules and -FP-injective modules and use these modules and their character modules to characterize some rings, including artinian, noetherian and coherent rings.
Although everything seems to oppose the two mathematicians, Charles Hermite’s role was crucial in the study and diffusion of Évariste Galois’s results in France during the second half of the nineteenth century. The present article examines that part of Hermite’s work explicitly linked to Galois, the reduction of modular equations in particular. It shows how Hermite’s mathematical convictions—concerning effectiveness or the unity of algebra, analysis and arithmetic—shaped his interpretation of Galois...