Displaying 161 – 180 of 639

Showing per page

Closure Theorem for Partially Semialgebraic Sets

María-Angeles Zurro (2007)

Bulletin of the Polish Academy of Sciences. Mathematics

In 1988 it was proved by the first author that the closure of a partially semialgebraic set is partially semialgebraic. The essential tool used in that proof was the regular separation property. Here we give another proof without using this tool, based on the semianalytic L-cone theorem (Theorem 2), a semianalytic analog of the Cartan-Remmert-Stein lemma with parameters.

Clôture intégrale des idéaux et équisingularité

Monique Lejeune-Jalabert, Bernard Teissier (2008)

Annales de la faculté des sciences de Toulouse Mathématiques

This text has two parts. The first one is the essentially unmodified text of our 1973-74 seminar on integral dependence in complex analytic geometry at the Ecole Polytechnique with J-J. Risler’s appendix on the Łojasiewicz exponents in the real-analytic framework. The second part is a short survey of more recent results directly related to the content of the seminar.The first part begins with the definition and elementary properties of the ν ¯ order function associated to an ideal I of a reduced analytic...

Cluster ensembles, quantization and the dilogarithm

Vladimir V. Fock, Alexander B. Goncharov (2009)

Annales scientifiques de l'École Normale Supérieure

A cluster ensemble is a pair ( 𝒳 , 𝒜 ) of positive spaces (i.e. varieties equipped with positive atlases), coming with an action of a symmetry group Γ . The space 𝒜 is closely related to the spectrum of a cluster algebra [12]. The two spaces are related by a morphism p : 𝒜 𝒳 . The space 𝒜 is equipped with a closed 2 -form, possibly degenerate, and the space 𝒳 has a Poisson structure. The map p is compatible with these structures. The dilogarithm together with its motivic and quantum avatars plays a central role...

Codes de Goppa

Jean-Francis MICHON (1983/1984)

Seminaire de Théorie des Nombres de Bordeaux

Codimension 1 subvarieties g and real gonality of real curves

Edoardo Ballico (2003)

Czechoslovak Mathematical Journal

Let g be the moduli space of smooth complex projective curves of genus g . Here we prove that the subset of g formed by all curves for which some Brill-Noether locus has dimension larger than the expected one has codimension at least two in g . As an application we show that if X g is defined over , then there exists a low degree pencil u X 1 defined over .

Codimension 3 Arithmetically Gorenstein Subschemes of projective N -space

Robin Hartshorne, Irene Sabadini, Enrico Schlesinger (2008)

Annales de l’institut Fourier

We study the lowest dimensional open case of the question whether every arithmetically Cohen–Macaulay subscheme of N is glicci, that is, whether every zero-scheme in 3 is glicci. We show that a general set of n 56 points in 3 admits no strictly descending Gorenstein liaison or biliaison. In order to prove this theorem, we establish a number of important results about arithmetically Gorenstein zero-schemes in 3 .

Codimension two transcendental submanifolds of projective space

Wojciech Kucharz, Santiago R. Simanca (2010)

Annales de l’institut Fourier

We provide a simple characterization of codimension two submanifolds of n ( ) that are of algebraic type, and use this criterion to provide examples of transcendental submanifolds when n 6 . If the codimension two submanifold is a nonsingular algebraic subset of n ( ) whose Zariski closure in n ( ) is a nonsingular complex algebraic set, then it must be an algebraic complete intersection in n ( ) .

Currently displaying 161 – 180 of 639