An explicit representation for ideal CR submanifolds of a complex hyperbolic space has been derived in T. Sasahara (2002). We simplify and reformulate the representation in terms of certain Kähler submanifolds. In addition, we investigate the almost contact metric structure of ideal CR submanifolds in a complex hyperbolic space. Moreover, we obtain a codimension reduction theorem for ideal CR submanifolds in a complex projective space.
In this paper we prove the implicit function theorem for locally blow-analytic functions, and as an interesting application of using blow-analytic homeomorphisms, we describe a very easy way to resolve singularities of analytic curves.
Let be a desingularization of a normal surface . The group Pic is provided with an order relation , defined by . for any effective exceptional divisor . Comparing to the usual order relation we define the ceiling of which is an exceptional divisor. This notion allows us to improve the usual vanishing theorem and we deduce from it a numerical criterion for rationality and a genus formula for a curve on a normal surface; the difficulty lies in the case of a Weil divisor which is not a Cartier...
Completeness of a dilation system on the standard Lebesgue space is considered for 2-periodic functions . We show that the problem is equivalent to an open question on cyclic vectors of the Hardy space on the Hilbert multidisc . Several simple sufficient conditions are exhibited, which include however practically all previously known results (Wintner; Kozlov; Neuwirth, Ginsberg, and Newman; Hedenmalm, Lindquist, and Seip). For instance, each of the following conditions implies cyclicity...
Nous considérons un germe de feuilletage holomorphe singulier non-dicritique défini sur une boule fermée , satisfaisant des hypothèses génériques, de courbe de séparatrice . Nous démontrons l’existence d’un voisinage ouvert de dans tel que, pour toute feuille de , l’inclusion naturelle induit un monomorphisme au niveau du groupe fondamental. Pour cela, nous introduisons la notion géométrique de « connexité feuilletée » avec laquelle nous réinterprétons la notion d’incompressibilité....