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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

O produto tensorial não abeliano de grupos e aplicações

Figueiredo, Gustavo Cazzeri Innocencio 22 April 2015 (has links)
Submitted by Izabel Franco (izabel-franco@ufscar.br) on 2016-09-23T19:38:10Z No. of bitstreams: 1 DissGCIF.pdf: 1709329 bytes, checksum: 237db6a30fde160e22a9171ebb48cdb8 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-26T20:45:16Z (GMT) No. of bitstreams: 1 DissGCIF.pdf: 1709329 bytes, checksum: 237db6a30fde160e22a9171ebb48cdb8 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-26T20:45:22Z (GMT) No. of bitstreams: 1 DissGCIF.pdf: 1709329 bytes, checksum: 237db6a30fde160e22a9171ebb48cdb8 (MD5) / Made available in DSpace on 2016-09-26T20:45:29Z (GMT). No. of bitstreams: 1 DissGCIF.pdf: 1709329 bytes, checksum: 237db6a30fde160e22a9171ebb48cdb8 (MD5) Previous issue date: 2015-04-22 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / The nonabelian tensor square GG of a group G was introduced by R. K. Dennis [8] in a search for new homology functors having a close relationship to K-theory and it is based on the work of C. Miller [14]. Subsequently R. Brown and J.-L. Loday [6] discovered a topological significance for the tensor square, namely, that the third homotopy group of the suspension of an Eilenberg MacLane space K(G; 1) satisfies _3 �����SK(G; 1) _ _= ker(_1), where _1 : GG ! G is the “comutator homomorphism”: _1(gh) = [g; h] = ghg�����1h�����1, 8g; h 2 G. They also defined the tensor product GH of two distinct groups acting “compatibly” on each other and showed that it arose in a certain “universal crossed square”. The main purpose of this work is to present the first properties of the nonabelian tensor product of groups and its applications in homotopy theory. / O quadrado tensorial não-abeliano GG de um grupo G foi introduzido por R. K. Dennis [8] em uma busca por novos funtores de homologia tendo uma íntima relação com a K-teoria e é baseado no trabalho de C. Miller [14]. Após isso, R. Brown e J.-L. Loday [6] descobriram uma importância topológica para o quadrado tensorial, a saber, que o terceiro grupo de homotopia da suspensão de um espaço de Eilenberg MacLane K(G; 1) satisfaz _3 SK(G; 1) __= ker(_1), em que _1 : G G ! G é o “homomorfismo comutador”: _1(gh) = [g; h] = ghg1h1, 8g; h 2 G. Os autores também definiram o produto tensorial GH de dois grupos quaisquer agindo “compativelmente” um no outro e mostraram que este aparece em um certo “quadrado cruzado universal”. O objetivo desse trabalho é apresentar o produto tensorial de grupos não-abelianos, suas primeiras propriedades e a aplicação dele na teoria de homotopia. / Processo 2013/01245-7
32

Une description fonctorielle des K-théories de Morava des 2-groupes abéliens élémentaires / A functorial description of the Morava K-theories of elementary abelian 2-groups

Nguyen, Le Chi Quyet 07 July 2017 (has links)
Le but de cette thèse est l'étude, d'un point de vue fonctoriel, des K-théories de Morava modulo 2 des 2-groupes abéliens élémentaires. Autrement dit, nous étudions les foncteurs covariants $V \mapsto K(n)^*(BV^{\sharp})$ pour le premier p=2 et n un entier positif.Le cas n=1, qui résulte directement du travail d'Atiyah sur la K-théorie topologique, nous donne un foncteur coanalytique qui ne possède aucun sous-foncteur polynomial non-constant. Il est très différent du cas n>1, où les foncteurs mentionnés ci-dessus s'avèrent être analytiques.La théorie de Henn-Lannes-Schwartz fournit une correspondance entre les foncteurs analytiques et les modules instables sur l'algèbre de Steenrod. Nous déterminons le module instable correspondant au foncteur analytique $V \mapsto K(2)^*(BV^{\sharp})$, en étudiant la relation entre ce foncteur et la structure d'anneau de Hopf de l'homologie de l'omega-spectre associé à la théorie K(2). / The aim of this PhD thesis is to study, from a functorial point of view, the mod 2 Morava K-theories of elementary abelian 2-groups. Namely, we study the covariant functors $V \mapsto K(n)^*(BV^{\sharp})$ for the prime p=2 and n a positive integer.The case n=1, which follows directly from the work of Atiyah on topological K-theory, gives us a coanalytic functor which contains no non-constant polynomial sub-functor. This is very different from the case n>1, where the above-mentioned functors are analytic.The theory of Henn-Lannes-Schwartz provides a correspondence between analytic functors and unstable modules over the Steenrod algebra. We determine the unstable module corresponding to the analytic functor $V \mapsto K(2)^*(BV^{\sharp})$, by studying the relation between this functor and the Hopf ring structure of the homology of the omega-spectrum associated to the theory K(2).
33

Groupe de Picard des groupes unipotents sur un corps quelconque / Picard groups of unipotent algebraic groups over an arbitrary field

Achet, Raphaël 25 September 2017 (has links)
Soit k un corps quelconque. Dans cette th±se, on étudie le groupe de Picard des k-groupes algébriques unipotents (lisses et connexes).Tout k-groupe algébrique unipotent est extension itérée de formes du groupe additif; on va donc d'abord s'intéresser au groupe de Picard des formes du groupe additif. L'étude de ce groupe est faite avec une méthode géométrique qui permet de traiter le cas plus général des formes de la droite affine. On obtient ainsi une borne explicite sur la torsion du groupe de Picard desformes de la droite affine et sur la torsion de la composante neutre du foncteur de Picard de leur complétion régulière. De plus, on trouve une condition suffisante pour que le groupe de Picard d'une forme de la droite affinesoit non trivial et on construit des exemples de formes non triviales de la droite affine dont le groupe de Picard est trivial.Un k-groupe algébrique unipotent est une forme de l'espace affine. Afin d'étudier le groupe de Picard d'une forme X de l'espace affine avec une méthode géométrique, on définit un foncteur de Picard "restreint". On montre que si X admet une complétion régulière, alors le foncteur de Picard "restreint" est représentable par un k-groupe unipotent (lisse, non nécessairement connexe).Avec ce foncteur de Picard "restreint" et des raisonnements purement géométriques, on obtient que le groupe de Picard d'une forme unirationnelle de l'espace affine est fini. De plus, on généralise un résultat dû à B. Totaro: si k est séparablement clos, et si le groupe de Picard d'un k-groupe algébrique unipotent commutatif est non trivial, alors il admet une extension non triviale par le groupe multiplicatif. / Let k be any field. In this Ph.D. dissertation we study the Picard group of the (smooth connected) unipotent k-algebraic groups.As every unipotent algebraic group is an iterated extension of forms of the additive group, we will study the Picard group of the forms of the additive group. In fact we study the Picard group of forms of the additive group and the affine line simultaneously using a geometric method. We obtain anexplicit upper bound on the torsion of the Picard group of the forms of the affine line and their regular completion, and a sufficient condition for the Picard group of a form of the affine line to be nontrivial. We also give examples of nontrivial forms of the affine line with trivial Picard groups.In general, a unipotent k-algebraic group is a form of the affine n-space. In order to study the Picard group of a form X of the affine n-space with a geometric method, we define a "restricted" Picard functor; we show that if X admits a regular completion then the "restricted" Picard functor is representable by a unipotent k-algebraic group (smooth, not necessarly connected). With this "restricted" Picard functor and geometric arguments we show that the Picard group of a unirational form of the affine n-space is finite. Moreover we generalise a result of B. Totaro: if k is separablyclosed and if the Picard group of a unipotent k-algebraic group is nontrivial then it admits a nontrivial extension by the multiplicative group.
34

Projective limits of weighted (LB) - spaces of holomorphic functions

WEGNER, SVEN-AKE 26 July 2010 (has links)
Los límites proyectivos de límites inductivos de espacios de Banach, también llamados espacios (PLB), surgen de forma natural en el análisis matemático. En esta tesis estudiamos espacios (PLB), cuyos bloques de construcción son espacios de Banach de funciones holomorfas definidas por normas supremo ponderadas. El estudio de estos espacios extiende la investigación de Agethen, Bierstedt, Bonet quienes han considerado recientemente espacios (PLB) ponderados de funciones continuas. Desde otra perspectiva, extiende la investigación de límites inductivos ponderados de espacios de Banach de funciones holomorfas, los cuales han sido analizados intensamente por varios autores los últimos años. Nuestro propósito es estudiar las propiedades localmente convexas de los espacios descritos arriba. En particular, investigamos cuando son ultrabornológicos o tonelados. Además, investigamos bajo qué circunstancias se pueden intercambiar el límite proyectivo y el inductivo y por lo tanto el espacio (PLB) coincide con el límite inductivo de espacios de Fréchet definidos por la misma sucesión; espacios de este último tipo has sido investigados por Bierstedt, Bonet. Probamos condiciones necesarias para las propiedades de los espacios antes mencionadas bajo hipótesis muy poco restrictivas. En cuanto a condiciones suficientes usamos métodos homológicos, cuya exploración fue iniciada por Palamodov al final de los sesenta y continuada por Vogt, Wengenroth y otros a lo largo de los últimos 40 años. Presentamos también un criterio para decidir si los espacios son tonelados adaptado a estas situaciones. No obstante, parece ser inevitable descomponer funciones holomorfas para probar cualquier resultado relativo a a las condiciones suficientes. Por lo tanto introducimos varios contextos en los cuales lo último es posible, dentro de estos contextos conseguimos la descomposición de diferentes formas; es decir, por descomposición de polinomios (en el disco y en el espacio), un método conectado con la teoría de proyecciones de Bergman, dos tipos de representaciones del espacio de sucesiones y el método de Hörmander. Bajo algunas hipótesis adicionales (satisfechas, como mostramos, por muchos ejemplos) damos en casi todos los contextos mencionados anteriormente unas caracterizaciones completas de cuándo el espacio es ultrabornológico, cuándo es tonelado y cuándo los límites inductivo y projectivo son intercambiables. Para finalizar nuestra investigación de espacios (PLB) ponderados, presentamos dos resultados que muestran que espacios de este tipo se pueden escribir en algunos casos como el producto tensorial de un espacio de Fréchet y un espacio (DF). El segundo resultado acerca de representaciones de productos tensoriales muestra que algunos espacios de ultradistribuciones (introducidos recientemente por Schmets y Valdivia) resultan ser espacios-(PLB) ponderados de funciones holomorfas. / Wegner, S. (2010). Projective limits of weighted (LB) - spaces of holomorphic functions [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/8480 / Palancia
35

Reasoning about big data flows : TOM4A recursive abstraction based problem solving method / Raisonnement sur les grands flux de données : méthode de résolution de problèmes basée sur l'abstraction récursive TOM4A

Vilar, Fabien 21 December 2018 (has links)
Ce document concerne le développement d'un cadre mathématique spécifiant une technologie capable de prendre en charge quelques unes des problématiques relevant du domaine des grands flux de données. Nous proposons de combiner le point de vue ontologique de Newell et celui épistémologique de Floridi d'abstraction pour construire des outils de transformation de modéles au moyen d'un ensemble adéquats de foncteurs au sens de la théorie des catégories de Samuel Eilenberg et Saunders Mac Lane. La méthode de résolution de problème proposée est basée sur un raisonnement d'abstraction temps réel qui produit, en ligne, une réduction d'un grand nombre de données sémantiquement pauvres en une donnée unique équivalente mais sémantiquement plus riche. Le prix à payer pour un tel enrichissement sémantique de l'information est la perte d'information syntaxique (i.e. le phénoméne d'oubli). Nos contributions sont les suivantes: (i) la démonstration que le concept d'observateur unaire de la théorie des observations datées (TOT) de Le Goc joue le même rôle qu'un échantillonneur de Dirac, (ii) la construction de la catégorie $TOT(\mathbb{Z})$, adéquate à la formulation du processus d'abstraction proposé et (iii) la conception de la méthode de résolution de problème TOM4A (timed observations methodology for abstraction) dont une application concrète est présentée visant à découvrir et modéliser le problème complexe de la fraude interne dans le domaine bancaire / This document concerns the development of a theoretical mathematical framework to provide a technology able to manage some of the problematics of the big data flows domain. We propose to combine Newell's ontological and Floridi's epistemological point of views of abstraction to build tools that transform models by the mean of an adequate set of functors according to Samuel Eilenberg and Saunders Mac Lane's category theory. The proposed problem solving method relies on a real time abstraction reasoning process to resume, on line, a lot of semantically poor data into an equivalent but richer one. The price to pay for such an information semantic enrichment is the loss of syntactic data (i.e. the oversight phenomenon). Our contributions are (i) to prove that Le Goc's timed observations theory (TOT) concept of unary observer plays the same role as Dirac's sampler, (ii) the construction of the $TOT(\mathbb{Z})$ category that is adequate to formulate the proposed abstraction based PSM and (iii) the design of TOM4A (timed observations methodology for abstraction), a specific recursive abstraction-reification based PSM whose a concrete application has been provided for detecting and modeling the complex problem of internal frauds in the banking industry
36

Algebraická a kripkovská sémantika substrukturálních logik / Algebraic and Kripke semantics of substructural logics

Arazim, Pavel January 2011 (has links)
This thesis is about the distributive full Lambek calculus, i.e., intuicionistic logic without the structural rules of exchange, contraction and weakening and particularly about the two semantics of this logic, one of which is algebraic, the other one is a Kripke semantic. The two semantics are treated in separate chapters and some results about them are shown, for example the disjunction property is proven by amalgamation of Kripke models. The core of this thesis is nevertheless the relation of these two semantics, since it is interesting to study what do they have in common and how can they actually differ, both being a semantics of the same logic. We show how to translate frames to algebras and algebras to frames, and, moreover, we extend such translation to morphisms, thus constructing two functors between the two categories. Key words:distributive FL logic, distributive full Lambek calculus, structural rules, distributive residuated lattice, Kripke frames, frame morphisms, category, functor 2
37

Equações de onda generalizadas e quantização funtorial para teorias de campo escalar livre / Generalized wave equations and functorial quantization for free scalar field theories.

Vasconcellos, João Braga de Góes e 07 April 2016 (has links)
Nesta dissertação apresentamos um método de quantização matemática e conceitualmente rigoroso para o campo escalar livre de interações. Trazemos de início alguns aspéctos importantes da Teoria de Distribuições e colocamos alguns pontos de geometria Lorentziana. O restante do trabalho é dividido em duas partes: na primeira, estudamos equações de onda em variedades Lorentzianas globalmente hiperbólicas e apresentamos o conceito de soluções fundamentais no contexto de equações locais. Em seguida, progressivamente construímos soluções fundamentais para o operador de onda a partir da distribuição de Riesz. Uma vez estabelecida uma solução para a equação de onda em uma vizinhança de um ponto da variedade, tratamos de construir uma solução global a partir da extensão do problema de Cauchy a toda a variedade, donde as soluções fundamentais dão lugar aos operadores de Green a partir da introdução de uma condição de contorno. Na última parte do trabalho, apresentamos um mínimo da Teoria de Categorias e Funtores para utilizar esse formalismo na contrução de um funtor de segunda quantização entre a categoria de variedades Lorentzianas globalmente hiperbólicas e a categoria de redes de álgebras C* satisfazendo os axiomas de Haag-Kastler. Ao fim, retomamos o caso particular do campo escalar quântico livre. / In this thesis we present a both mathematical and conceptually rigorous quantization method for the neutral scalar field free of interactions. Initially, we introduce some aspects of the Theory of Distributions and we establish some points of Lorentzian geometry. The rest of the work is divided in two parts: in the first one, we study wave equations on globally hyperbolic Lorentzian manifolds, hence presenting the concept of fundamental solutions within the context of locally defined wave equations. Next, we progressively construct fundamental solutions for the wave operator from the Riesz distribution. Once established a solution to the wave equation in a neighbourhood of a point of the manifold, we move forward to produce a global solution from the extension of the Cauchy problem to the whole manifold. At this stage, fundamental solutions are replaced by Green\'s operators by the imposition of appropriate boundary conditions. In the last part, we present a minimum on the Theory of Categories and Functors. This is followed by the use of this formalism in the development of a second-quantization functor between the category of Lorentzian globally hyperbolic manifolds and the category of nets of C*-algebras obeying Haag-Kastler axioms. Finally, we turn our attention to the particular case of the quantum free scalar field.
38

Homomorphismes de type Johnson pour les surfaces et invariant perturbatif universel des variétés de dimension trois / Johnson-type homomorphisms for surfaces and the universal perturbative invariant of 3-manifolds

Vera Arboleda, Anderson Arley 28 June 2019 (has links)
Soit Σ une surface compacte connexe orientée avec une seule composante du bord. Notons par M le groupe d'homéotopie de Σ. En considérant l'action de M sur le groupe fondamental de Σ, il est possible de définir différentes filtrations de M ainsi que des homomorphismes sur chaque terme de ces filtrations. Le but de cette thèse est double. En premier lieu, nous étudions deux filtrations de M : la " filtration de Johnson-Levine " introduite par Levine et la " filtration de Johnson alternative " introduite recemment par Habiro et Massuyeau. Les définitions de ces deux filtrations prennent en compte un corps en anses bordé par la surface. Nous nous référons à ces filtrations comme " filtrations de type Johnson " et les homomorphismes correspondants sont appelés " homomorphismes de type Johnson " par leur analogie avec la filtration de Johnson originale et les homomorphismes de Johnson usuels. Nous donnons une comparaison de la filtration de Johnson avec la filtration de Johnson-Levine au niveau du monoïde des cobordismes d'homologie de Σ. Nous donnons également une comparaison entre la filtration de Johnson alternative, la filtration Johnson-Levine et la filtration de Johnson au niveau du groupe d'homéotopie. Deuxièmement, nous étudions la relation entre les " homomorphismes de type Johnson" et l'extension fonctorielle de l'invariant perturbatif universel des variétés de dimension trois (l'invariant de Le-Murakami-Ohtsuki ou invariant LMO). Cette extension fonctorielle s'appelle le foncteur LMO et il prend ses valeurs dans une catégorie de diagrammes. Nous démontrons que les "homomorphismes de type Johnson " peuvent être lus dans la réduction arborée du foncteur LMO. En particulier, cela fournit une nouvelle grille de lecture de la réduction arborée du foncteur LMO. / Let Σ be a compact oriented surface with one boundary component and let M denote the mapping class group of Σ. By considering the action of M on the fundamental group of Σ it is possible to define different filtrations of M together with some homomorphisms on each term of the filtrations. The aim of this thesis is twofold. First, we study two filtrations of M : the « Johnson-Levine filtration » introduced by Levine and « the alternative Johsnon filtration » introduced recently by Habiro and Massuyeau. The definition of both filtrations involve a handlebody bounded by Σ. We refer to these filtrations as ≪ Johnson-type filtrations » and the corresponding homomorphisms have referred to as « Johnson-type homomorphisms » by their analogy with the original Johnson filtration and the usual Johnson homomorphisms. We provide a comparison of the Johnson filtration with the Johnson-Levine filtration at the level of the monoid of homology cobordisms of Σ. We also provide a comparison of the alternative Johnson filtration with the Johnson-Levine filtration and the Johnson filtration at the level of the mapping class group. Secondly, we study the relationship between the « Johnson-type homomorphisms » and the functorial extension of the universal perturbative invariant of 3-manifolds (the Le-Murakami-Ohtsuki invariant or LMO invariant). This functorial extension is calling the LMO functor and it takes values in a category of diagrams. We prove that the « Johnson-type homomorphisms » is in the tree reduction of the LMO functor. In particular, this provides a new reading grid of the tree reduction of the LMO functor.
39

Equações de onda generalizadas e quantização funtorial para teorias de campo escalar livre / Generalized wave equations and functorial quantization for free scalar field theories.

João Braga de Góes e Vasconcellos 07 April 2016 (has links)
Nesta dissertação apresentamos um método de quantização matemática e conceitualmente rigoroso para o campo escalar livre de interações. Trazemos de início alguns aspéctos importantes da Teoria de Distribuições e colocamos alguns pontos de geometria Lorentziana. O restante do trabalho é dividido em duas partes: na primeira, estudamos equações de onda em variedades Lorentzianas globalmente hiperbólicas e apresentamos o conceito de soluções fundamentais no contexto de equações locais. Em seguida, progressivamente construímos soluções fundamentais para o operador de onda a partir da distribuição de Riesz. Uma vez estabelecida uma solução para a equação de onda em uma vizinhança de um ponto da variedade, tratamos de construir uma solução global a partir da extensão do problema de Cauchy a toda a variedade, donde as soluções fundamentais dão lugar aos operadores de Green a partir da introdução de uma condição de contorno. Na última parte do trabalho, apresentamos um mínimo da Teoria de Categorias e Funtores para utilizar esse formalismo na contrução de um funtor de segunda quantização entre a categoria de variedades Lorentzianas globalmente hiperbólicas e a categoria de redes de álgebras C* satisfazendo os axiomas de Haag-Kastler. Ao fim, retomamos o caso particular do campo escalar quântico livre. / In this thesis we present a both mathematical and conceptually rigorous quantization method for the neutral scalar field free of interactions. Initially, we introduce some aspects of the Theory of Distributions and we establish some points of Lorentzian geometry. The rest of the work is divided in two parts: in the first one, we study wave equations on globally hyperbolic Lorentzian manifolds, hence presenting the concept of fundamental solutions within the context of locally defined wave equations. Next, we progressively construct fundamental solutions for the wave operator from the Riesz distribution. Once established a solution to the wave equation in a neighbourhood of a point of the manifold, we move forward to produce a global solution from the extension of the Cauchy problem to the whole manifold. At this stage, fundamental solutions are replaced by Green\'s operators by the imposition of appropriate boundary conditions. In the last part, we present a minimum on the Theory of Categories and Functors. This is followed by the use of this formalism in the development of a second-quantization functor between the category of Lorentzian globally hyperbolic manifolds and the category of nets of C*-algebras obeying Haag-Kastler axioms. Finally, we turn our attention to the particular case of the quantum free scalar field.
40

Prolongement de faisceaux inversibles

Pepin, Cédric 30 June 2011 (has links)
Soit R un anneau de valuation discrète de corps de fractions K. Soit X_K un K- schéma propre géométriquement normal. On montre que X_K possède des modèles X sur R, propres, plats, normaux et tels que tout faisceau inversible sur X_K se prolonge en un faisceau inversible sur X. On peut alors reconstruire le modèle de Néron de la variété de Picard de X_K, à partir du foncteur de Picard de X/R.Lorsque R est hensélien à corps résiduel algébriquement clos, on en tire des informations sur le prolongement de l’équivalence algébrique de X_K à X. En particulier, on peut décrire le symbole de Néron entre 0-cycles de degré zéro et diviseurs algébriquement équivalents à zéro sur X_K, en termes de multiplicités d’intersection sur le modèle X. Ceci nous permet de reformuler la conjecture de dualité de Grothendieck pour les modèles de Néron des variétés abéliennes, en termes d’équivalence algébrique relative. / Let R be a discrete valuation ring with fraction field K. Let X_K be proper geometrically normal scheme over K. One shows that X_K admits models X over R which are proper, flat, normal an such that any invertible sheaf on X_K can be extended to an invertible sheaf on X. Then, one can recover the Néron model of the Picard variety of X_K from the Picard functor of X/R.When R is henselian with algebraically closed residue field, one obtains some consequences about the extension of algebraic equivalence from X_K to X. In particular, one can describe the Néron symbol between 0-cycles of degree zero and divisors which are algebraically equivalent to zero on X_K, in terms of intersection multiplicities on the model X. This allows us to reformulate Grothendieck’s duality conjecture for Néron models of abelian varieties, in terms of relative algebraic equivalence.

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