Miyanishi's characterization of the affine 3-space does not hold in higher dimensions
We present an example which confirms the assertion of the title.
We present an example which confirms the assertion of the title.
Let be a commutative ring with identity. We study the concept of strongly 1-absorbing primary ideals which is a generalization of -ideals and a subclass of -absorbing primary ideals. A proper ideal of is called strongly 1-absorbing primary if for all nonunit elements such that , it is either or . Some properties of strongly 1-absorbing primary ideals are studied. Finally, rings over which every semi-primary ideal is strongly 1-absorbing primary, and rings over which every strongly...
Let be a commutative ring with non-zero identity. Various properties of multiplication modules are considered. We generalize Ohm’s properties for submodules of a finitely generated faithful multiplication -module (see [8], [12] and [3]).
The class of loop spaces of which the mod cohomology is Noetherian is much larger than the class of -compact groups (for which the mod cohomology is required to be finite). It contains Eilenberg–Mac Lane spaces such as and 3-connected covers of compact Lie groups. We study the cohomology of the classifying space of such an object and prove it is as small as expected, that is, comparable to that of . We also show that X differs basically from the classifying space of a -compact group...