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Decomposition into special cubes and its applications to quasi-subanalytic geometry

Krzysztof Jan Nowak (2009)

Annales Polonici Mathematici

The main purpose of this paper is to present a natural method of decomposition into special cubes and to demonstrate how it makes it possible to efficiently achieve many well-known fundamental results from quasianalytic geometry as, for instance, Gabrielov's complement theorem, o-minimality or quasianalytic cell decomposition.

Definable stratification satisfying the Whitney property with exponent 1

Beata Kocel-Cynk (2007)

Annales Polonici Mathematici

We prove that for a finite collection of sets A , . . . , A s k + n definable in an o-minimal structure there exists a compatible definable stratification such that for any stratum the fibers of its projection onto k satisfy the Whitney property with exponent 1.

Densité des ensembles sous-analytiques

Krzysztof Kurdyka, Gilles Raby (1989)

Annales de l'institut Fourier

It is shown that a sub-analytic set has a density at each point, and the notion of pure cone is defined. As in the complex case, this density may be expressed in terms of the area of the connected components of the pure tangent cone, with involved integral multiplicities.

Density of Morse functions on sets definable in o-minimal structures

Ta Lê Loi (2006)

Annales Polonici Mathematici

We present a tameness property of sets definable in o-minimal structures by showing that Morse functions on a definable closed set form a dense and open subset in the space of definable C p functions endowed with the Whitney topology.

Directional properties of sets definable in o-minimal structures

Satoshi Koike, Ta Lê Loi, Laurentiu Paunescu, Masahiro Shiota (2013)

Annales de l’institut Fourier

In a previous paper by Koike and Paunescu, it was introduced the notion of direction set for a subset of a Euclidean space, and it was shown that the dimension of the common direction set of two subanalytic subsets, called the directional dimension, is preserved by a bi-Lipschitz homeomorphism, provided that their images are also subanalytic. In this paper we give a generalisation of the above result to sets definable in an o-minimal structure on an arbitrary real closed field. More precisely, we...

Distance géodésique sur un sous-analytique.

Krzystof Kurdyka, Patrice Orro (1997)

Revista Matemática de la Universidad Complutense de Madrid

Pour un ensemble sous-analytique, connexe fermé, la distance géodésique est atteinte et est uniformément équivalente, avec des constantes arbitrairement proches de 1, à une distance sous-analytique.

Équisingularité réelle II : invariants locaux et conditions de régularité

Georges Comte, Michel Merle (2008)

Annales scientifiques de l'École Normale Supérieure

On définit, pour un germe d’ensemble sous-analytique, deux nouvelles suites finies d’invariants numériques. La première a pour termes les localisations des courbures de Lipschitz-Killing classiques, la seconde est l’équivalent réel des caractéristiques évanescentes complexes introduites par M. Kashiwara. On montre que chaque terme d’une de ces suites est combinaison linéaire des termes de l’autre, puis on relie ces invariants à la géométrie des discriminants des projections du germe sur des plans...

Examples of functions -extendable for each finite, but not -extendable

Wiesław Pawłucki (1998)

Banach Center Publications

In Example 1, we describe a subset X of the plane and a function on X which has a k -extension to the whole 2 for each finite, but has no -extension to 2 . In Example 2, we construct a similar example of a subanalytic subset of 5 ; much more sophisticated than the first one. The dimensions given here are smallest possible.

Extending analyticK-subanalytic functions

Artur Piękosz (2004)

Open Mathematics

Letg:U→ℝ (U open in ℝn) be an analytic and K-subanalytic (i. e. definable in ℝanK, whereK, the field of exponents, is any subfield ofℝ) function. Then the set of points, denoted Σ, whereg does not admit an analytic extension is K-subanalytic andg can be extended analytically to a neighbourhood of Ū.

Extending Tamm's theorem

Lou van den Dries, Chris Miller (1994)

Annales de l'institut Fourier

We extend a result of M. Tamm as follows:Let f : A , A m + n , be definable in the ordered field of real numbers augmented by all real analytic functions on compact boxes and all power functions x x r : ( 0 , ) , r . Then there exists N such that for all ( a , b ) A , if y f ( a , y ) is C N in a neighborhood of b , then y f ( a , y ) is real analytic in a neighborhood of b .

Finiteness property for generalized abelian integrals

Rémi Soufflet (2003)

Annales de l’institut Fourier

We study the integrals of real functions which are finite compositions of globally subanalytic maps and real power functions. These functions have finiteness properties very similar to those of subanalytic functions. Our aim is to investigate how such finiteness properties can remain when taking the integrals of such functions. The main result is that for almost all power maps arising in a x λ -function, its integration leads to a non-oscillating function. This can be seen as a generalization of Varchenko...

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