-flat and -FP-injective modules
In this paper, we study the existence of the -flat preenvelope and the -FP-injective cover. We also characterize -coherent rings in terms of the -FP-injective and -flat modules.
Nagata rings and directed unions of Artinian subrings.
Nagata's Criterion and Openness of Loci for Gorenstein and Complete Intersection.
Nash Wings and Real Prime Divisors.
Near solutions of polynomial equations
Néron models and tame ramification
New evidence for Green's conjecture on syzygies of canonical curves
Newton and Schinzel sequences in quadratic fields
We give the maximal length of a Newton or a Schinzel sequence in a quadratic extension of a global field. In the case of a number field, the maximal length of a Schinzel sequence is 1, except in seven particular cases, and the Newton sequences are also finite, except for at most finitely many cases, all real. We give the maximal length of these sequences in the special cases. We have similar results in the case of a quadratic extension of a function field , taking in account that the ring of integers...
Newton Polyhedra and Irreducibility.
Newton-Puiseux expansion and generalized Tschirnhausen transformation. I.
Nicht endlich erzeugte Primideale in Steinschen Algebren.
Nicht-ausgeartete reguläre Überlagerungen.
Noetherian loop spaces
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...
Noether-Lefschetz, space curves and mathematical instantons.
Noether's problem for some groups of order 16n
Noether's problem over an algebraically closed field.
Non commutative Krull domains.
Non-axiomatizability of real spectra in
We show that the property of a spectral space, to be a spectral subspace of the real spectrum of a commutative ring, is not expressible in the infinitary first order language of its defining lattice. This generalises a result of Delzell and Madden which says that not every completely normal spectral space is a real spectrum.
Noncoherence of a causal Wiener algebra used in control theory.
Noncommutative del Pezzo surfaces and Calabi-Yau algebras
The hypersurface in with an isolated quasi-homogeneous elliptic singularity of type , has a natural Poisson structure. We show that the family of del Pezzo surfaces of the corresponding type provides a semiuniversal Poisson deformation of that Poisson structure. We also construct a deformation-quantization of the coordinate ring of such a del Pezzo surface. To this end, we first deform the polynomial algebra to a noncommutative algebra with generators and the following 3 relations labelled...