Extreme Curves Bound Embedded Minimal Surfaces of the Type of the Disc.
Nous définissons deux notions nouvelles en géométrie analytique réelle, celle de fonction Nash-analytique et celle de faisceau semi-cohérent. Avec ces notions, nous obtenons des théorèmes de cohérence analogues à ceux du cas complexe (théorème de cohérence d’Oka, théorème de l’image directe, cohérence d’un ensemble analytique complexe).
A subsheaf of the sheaf of germs functions over an open subset of is called a sheaf of sub function. Comparing with the investigations of sheaves of ideals of , we study the finite presentability of certain sheaves of sub -rings. Especially we treat the sheaf defined by the distribution of Mather’s -classes of a mapping.
O’Grady showed that certain special sextics in called EPW sextics admit smooth double covers with a holomorphic symplectic structure. We propose another perspective on these symplectic manifolds, by showing that they can be constructed from the Hilbert schemes of conics on Fano fourfolds of degree ten. As applications, we construct families of Lagrangian surfaces in these symplectic fourfolds, and related integrable systems whose fibers are intermediate Jacobians.
In a paper written in 1876 [4], Felix Klein gave a formula relating the number of real flexes of a generic real plane projective curve to the number of real bitangents at non-real points and the degree, which shows in particular that the number of real flexes cannot exceed one third of the total number of flexes. We show that Klein's arguments can be made rigorous using a little of the theory of singularities of maps, justifying in particular his resort to explicit examples.
Si discute il comportamento asintotico di energie di tipo Ginzburg-Landau, per funzioni da in , e sotto l'ipotesi che l'esponente di crescita sia strettamente maggiore di . In particolare, si illustra un risultato di compattezza e di -convergenza, rispetto a una opportuna topologia sui Jacobiani, visti come correnti -dimensionali. L'energia limite è definita sulla classe degli -bordi interi , e la sua densità dipende localmente dalla molteplicità di tramite una famiglia di costanti di...
Let be M a smooth manifold, A a local algebra and a manifold of infinitely near points on M of kind A. We build the canonical foliation on and we show that the canonical foliation on the tangent bundle TM is the foliation defined by its canonical field.