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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.
11

On the Topology of Symmetric Semialgebraic Sets

Alison M Rosenblum (15354865) 27 April 2023 (has links)
<p>This work strengthens and extends an algorithm for computing Betti numbers of symmetric semialgebraic sets developed by Basu and Riener in, <em>Vandermonde Varieties, Mirrored Spaces, and the Cohomology of Symmetric Semi-Algebraic Sets</em>. We first adapt a construction of Gabrielov and Vorobjov in, <em>Approximation of Definable Sets by Compact Families, and Upper Bounds on Homotopy and Homology,</em> for replacing arbitrary definable sets by compact ones to the symmetric case. The original construction provided maps from the homotopy and homology groups of the replacement set to those of the original; we show that for sets symmetric relative to the action of some finite reflection group <em>G</em>, we may construct these maps to be equivariant. This modification to the construction for compact replacement allows us to extend Basu and Riener's theorem on which submodules appear in the isotypic decomposition of each cohomology space to sets not necessarily closed and bounded. Furthermore, by utilizing this equivariant compact approximation, we may obtain a precise description of the aforementioned decomposition of each cohomology space, and not merely the final dimension of the space, from Basu and Riener's algorithm.</p> <p><br></p> <p>    Though our equivariant compact replacement holds for <em>G</em> any finite reflection group, Basu and Riener's results only consider the case of the action the of symmetric group, sometimes termed type <em>A</em>. As a first step towards generalizing Basu and Riener's work, we examine the next major class of symmetry: the action of the group of signed permutations (known as type <em>B</em>). We focus our attention on Vandermonde varieties, a key object in Basu and Riener's proofs. We show that the intersection of a type <em>B</em> Vandermonde variety with a fundamental region of type <em>B</em> symmetry is topologically regular. We also prove a result about the intersection of a type <em>B</em> Vandermonde variety with the walls of this fundamental region, leading to the elimination of factors in a different decomposition of the homology spaces.</p>
12

Código MDS com a métrica POSET / MDS codes with the poset metric

Leocadio, Marcelo Augusto 30 July 2013 (has links)
Made available in DSpace on 2015-03-26T13:45:36Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1755688 bytes, checksum: 33e268f82618cf29e2d1fa6df5c6fa6c (MD5) Previous issue date: 2013-07-30 / Fundação de Amparo a Pesquisa do Estado de Minas Gerais / A poset metric is the generalization of the Hamming metric. In this work we make a detailed study of poset spaces, hierarchy of I -weights and I -distribution of P P weights, emphasizing the non-degenerate poset codes. We verify the duality relation between the hierarchy weights of poset code and its dual. In the sequel two new parameters are defined to a class of poset codes non-degenerate with dual code is too non-degenerate in the environment. As a result enunciated in the Minimality Theorem, the Variance Theorem and the Minimality Identity in the poset spaces. / Uma generalização da métrica de Hamming é a métrica poset. Faremos um estudo detalhado dos espaços poset, hierarquia de I-pesos e a I-distribuição de pesos, dando ênfase aos códigos poset não degenerados. Verificamos a relação de dualidade poset entre as hierarquias de um código e seu dual. Definimos dois novos parâmetros para a classe de códigos dualmente não degenerados no ambiente poset. Como consequência, enunciamos e mostramos o Teorema da Minimalidade, o Teorema da e Variância e a Identidade de Minimalidades no espaço poset.
13

Groupes linéaires définissables dans les corps p-adiques / Linear groups definable in p-adic fields

Druart, Benjamin 29 June 2015 (has links)
Cette thèse est consacrée à l’étude des groupes linéaires définissables dans les corpsp-adiques. Les tores anisotropes jouent un rôle central tout au long de ce travail. Nousdonnons une description modèle-théorique et algébrique des Qp-tores anisotropes dedimension 1.L’étude des sous-groupes de Cartan de SL2(Qp) (où Qp est un corps élémentairementéquivalent à Qp) nous permet de donner une description complète de tous les sous-groupes définissables de SL2(Qp).Nous nous intéressons également aux groupes linéaires définissables dans des enri-chissements p-minimaux d’un corps p-adiquement clos. Nous introduisons une notionde p-connexité pour les groupes. Et nous établissons que tout groupe linéaire com-mutatif p-connexe définissable dans une telle structure est isomorphe à un groupesemi-algébrique.Enfin des résultats sur la généricité et la générosité dans SL2(Qp) sont donnés. / This thesis is dedicated to the study of linear definable groups in p-adic fields. Ani-sotropic tori play an important role in this work. We give a model-theoretic andalgebraic description of anisotropic Qp-tori of dimension 1.The study of Cartan subgroups in SL2(Qp) (where Qp is a field elementarily equi-valent to Qp) permit us to give a complete description of all definable subgroups ofSL2(Qp).We are seeing also linear groups definable in p-minimal expansions of p-adically closedfields. We introduce a notion of p-connexity for groups. We etablish that every linearcommutative p-connected group definable in such structure is isomorphic to a semi-algebraic group.Finally some results on genericity and generosity in SL2(Qp) are given.
14

O-minimality, nonclassical modular functions and diophantine problems

Spence, Haden January 2018 (has links)
There now exists an abundant collection of conjectures and results, of various complexities, regarding the diophantine properties of Shimura varieties. Two central such statements are the Andre-Oort and Zilber-Pink Conjectures, the first of which is known in many cases, while the second is known in very few cases indeed. The motivating result for much of this document is the modular case of the Andre-Oort Conjecture, which is a theorem of Pila. It is most commonly viewed as a statement about the simplest kind of Shimura varieties, namely modular curves. Here, we tend instead to view it as a statement about the properties of the classical modular j-function. It states, given a complex algebraic variety V, that V contains only finitely many maximal special subvarieties, where a special variety is one which arises from the arithmetic behaviour of the j-function in a certain natural way. The central question of this thesis is the following: what happens if in such statements we replace the j-function with some other kind of modular function; one which is less well-behaved in one way or another? Such modular functions are naturally called nonclassical modular functions. This question, as we shall see, can be studied using techniques of o-minimality and point-counting, but some interesting new features arise and must be dealt with. After laying out some of the classical theory, we go on to describe two particular types of nonclassical modular function: almost holomorphic modular functions and quasimodular functions (which arise naturally from the derivatives of the j-function). We go on to prove some results about the diophantine properties of these functions, including several natural Andre-Oort-type theorems, then conclude by discussing some bigger-picture questions (such as the potential for nonclassical variants of, say, Zilber-Pink) and some directions for future research in this area.
15

Conjuntos minimais e caóticos em campos de vetores planares suaves por partes / Minimal and chaotic sets in planar piecewise smooth vector fields

Gazetta, Daniele Alessandra Reghini [UNESP] 06 January 2016 (has links)
Submitted by DANIELE ALESSANDRA REGHINI GAZETTA null (daniellygaze@hotmail.com) on 2016-01-15T17:36:23Z No. of bitstreams: 1 diss-daniele.pdf: 783553 bytes, checksum: e593f1ebb872fff02a080d05283744d5 (MD5) / Rejected by Ana Paula Grisoto (grisotoana@reitoria.unesp.br), reason: Solicitamos que realize uma nova submissão seguindo as orientações abaixo: No campo “Versão a ser disponibilizada online imediatamente” foi informado que seria disponibilizado o texto completo porém no campo “Data para a disponibilização do texto completo” foi informado que o texto completo deverá ser disponibilizado apenas 6 meses após a defesa. Caso opte pela disponibilização do texto completo apenas 6 meses após a defesa selecione no campo “Versão a ser disponibilizada online imediatamente” a opção “Texto parcial”. Esta opção é utilizada caso você tenha planos de publicar seu trabalho em periódicos científicos ou em formato de livro, por exemplo e fará com que apenas as páginas pré-textuais, introdução, considerações e referências sejam disponibilizadas. Se optar por disponibilizar o texto completo de seu trabalho imediatamente selecione no campo “Data para a disponibilização do texto completo” a opção “Não se aplica (texto completo)”. Isso fará com que seu trabalho seja disponibilizado na íntegra no Repositório Institucional UNESP. Por favor, corrija esta informação realizando uma nova submissão. Agradecemos a compreensão. on 2016-01-15T19:12:27Z (GMT) / Submitted by DANIELE ALESSANDRA REGHINI GAZETTA null (daniellygaze@hotmail.com) on 2016-01-16T16:43:56Z No. of bitstreams: 2 diss-daniele.pdf: 783553 bytes, checksum: e593f1ebb872fff02a080d05283744d5 (MD5) daniele-dissert.pdf: 585710 bytes, checksum: 222237614b39411bc9b9a3e82ad6ab17 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-01-18T16:33:44Z (GMT) No. of bitstreams: 1 gazetta_dar_me_sjrp.pdf: 783553 bytes, checksum: e593f1ebb872fff02a080d05283744d5 (MD5) / Made available in DSpace on 2016-01-18T16:33:44Z (GMT). No. of bitstreams: 1 gazetta_dar_me_sjrp.pdf: 783553 bytes, checksum: e593f1ebb872fff02a080d05283744d5 (MD5) Previous issue date: 2016-01-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O principal resultado dessa dissertação é o Teorema de Poincaré-Bendixson para campos de vetores planares suaves por partes, que nos diz quais são os tipos de conjuntos limite. Estudaremos também detalhes a respeito dos conceitos de conjuntos minimais e caóticos em campos de vetores planares suaves por partes. / The main result of this work is the Poincaré - Bendixson Theorem for planar piecewise smooth vector fields, which tell us what kind of limit sets arise in this context. We will also study details about the concepts of minimal and chaotic sets in planar piecewise smooth vector fields.
16

[pt] PROPRIEDADES TOPOLÓGICAS DE ATRATORES PARCIALMENTE HIPERBÓLICOS / [en] TOPOLOGICAL PROPERTIES OF PARTIALLY HYPERBOLIC ATTRACTORS

20 December 2021 (has links)
[pt] Neste trabalho estendemos os resultados em (12) e (22), sobre a minimalidade de uma das folheações estável ou instável forte), para o caso de atratores robustamente transitivos parcialmente hiperbólico e com direção central unidimensional. No nosso contexto a hiperbolicidade parcial esta definida somente no atrator. Algumas consequências são obtidas tais como a verificação de que estes atratores são robustamente) classes homoclínicas, possuem robustamente) interior vazio e admitem uma decomposição espectral. Resultados similares ainda valem no caso de atratores genericamente transitivos. / [en] In this work we extend the results in (12) and (22) about the minimality of one of the strong foliations (stable or unstable), for the case of robustly transitive attractors that is partially hyperbolic with one dimensional center bundle. In our context the partial hyperbolicity is defined only in the attractor. Some consequences are obtained as the verification that these attractors are (robustly) homoclinic classes, have (robustly) empty interior and admit a spectral decomposition. Similar results still holds in the case of generically transitive attractors.
17

Quasi-orders, C-groups, and the differentiel rank of a differential-valued field / Quasi-ordres, C-groupes, et rang différentiel d’un corps différentiel valué

Lehéricy, Gabriel 12 September 2018 (has links)
Cette thèse a pour objet les ordres, les valuations et les C-relations sur les groupes, ainsi que les corps différentiels valués tels qu’étudiés par Rosenlicht. Elle accomplit trois objectifs principaux. Le premier est d’introduire et d’étudier une notion de quasi-ordre sur les groupes qui a pour but de réunir les ordres et les valuations dans un même cadre. Nous donnons un théorème de structure des groupes munis d’un tel quasi-ordre, ce qui nous permet ensuite de donner un “théorème de plongement de Hahn” pour ces groupes. Le second objectif de cette thèse est de décrire les C-groupes à l’aide des quasi-ordres. Nous donnons un théorème de structure pour les C-groupes, qui énonce que tout C-groupe est un “mélange” de groupes ordonnés et de groupes valués. Nous utilisons ensuite ce résultat pour caractériser les groupes C-minimaux à l’intérieur de la classe des C-groupes. Le troisième objectif de cette thèse est d’introduire et d’étudier une notion de rang différentiel d’un corps différentiel valué. Nous définissons cette notion par analogie avec les notions de rang exponentiel d’un corps exponentiel et de rang de différence d’un corps aux différences. Nous montrons que cette notion de rang n’est pas tout à fait satisfaisante, et introduisons donc une meilleure notion de rang appelée le rang différentiel déployé. Nous donnons ensuite une méthode pour définir une dérivation “de type Hardy” sur un corps de séries formelles généralisées, ce qui nous permet de construire des corps différentiels valués dont le rang différentiel et le rang différentiel déployé ont été arbitrairement choisis. / This thesis deals with orders, valuations and C-relations on groups, and with differential-valued fields à la Rosenlicht. It achieves three main objectives. The first one is to introduce and study a notion of quasi-order on groups meant to encompass orders and valuations in a common framework. We give a structure theorem for groups endowed with such a quasi-order, which then allows us to give a “Hahn’s embedding theorem” for these groups. The second objective of this thesis is to describe C-groups via quasi-orders. We give a structure theorem for C-groups, which basically states that any C-group is a “mix” of ordered groups and valued groups. We then use this result to characterize C-minimal groups inside the class of C-groups. The third objective of this thesis is to introduce and study a notion of differential rank for differential-valued fields. We define this notion by analogy with the exponential rank of an exponential field and with the difference rank of a difference field. We show that this notion of rank is not quite satisfactory, so we introduce a better notion of rank called the unfolded differential rank. We then give a method to define “Hardy-type” derivations on fields of generalized power series, which allows us to build differential-valued fields of arbitrary given differential rank and unfolded differential rank.
18

Autour de la conjecture de Zilber-Pink pour les Variétés de Shimura / Around the Zilber-Pink Conjecture for Shimura Varieties

Ren, Jinbo 06 July 2018 (has links)
Dans cette thèse, nous nous intéressons à l'étude de l'arithmétique et de la géométrie des variétés de Shimura. Cette thèse s'est essentiellement organisée autour de trois volets. Dans la première partie, on étudie certaines applications de la théorie des modèles en théorie des nombres. En 2014, Pila et Tsimerman ont donné une preuve de la conjecture d'Ax-Schanuel pour la fonction j et, avec Mok, ont récemment annoncé une preuve de sa généralisation à toute variété de Shimura. Nous nous référons à cette généralisation comme à la conjecture d'Ax-Schanuel hyperbolique. Dans ce projet, nous cherchons à généraliser les idées de Habegger et Pila pour montrer que, sous un certain nombre d'hypothèses arithmétiques, la conjecture d'Ax-Schanuel hyperbolique implique, par une extension de la stratégie de Pila-Zannier, la conjecture de Zilber-Pink pour les variétés de Shimura. Nous concluons en vérifiant toutes ces hypothèses arithmétiques à l'exception d'une seule dans le cas d'un produit de courbes modulaires, en admettant la conjecture dite des grandes orbites de Galois. Il s'agit d'un travail en commun avec Christopher Daw. La seconde partie est consacrée à un résultat cohomologique en direction de la conjecture de Zilber-Pink. Étant donné un groupe algébrique semi-simple sur un corps de nombres F contenu dans ℝ, nous démontrons que deux sous-groupes algébriques semi-simples définis sur F sont conjugués sur F, si et seulement s'il le sont sur une extension réelle finie de F de degré majoré indépendamment des sous-groupes choisis. Il s'agit d'un travail en commun avec Mikhail Borovoi et Christopher Daw. La troisième partie étudie la distribution des variétés de Shimura compactes. On rappelle qu'une variété de Shimura S de dimension 1 est toujours compacte sauf si S est une courbe modulaire. Nous généralisons cette observation en définissant une fonction de hauteur dans l'espace des variétés de Shimura associée à un groupe réductif réel donné. Dans le cas des groupes unitaires, on prouve que la densité des variétés de Shimura non-compactes est nulle. / In this thesis, we study some arithmetic and geometric problems for Shimura varieties. This thesis consists of three parts. In the first part, we study some applications of model theory to number theory. In 2014, Pila and Tsimerman gave a proof of the Ax-Schanuel conjecture for the j-function and, with Mok, have recently announced a proof of its generalization to any (pure) Shimura variety. We refer to this generalization as the hyperbolic Ax-Schanuel conjecture. In this article, we show that the hyperbolic Ax-Schanuel conjecture can be used to reduce the Zilber-Pink conjecture for Shimura varieties to a problem of point counting. We further show that this point counting problem can be tackled in a number of cases using the Pila-Wilkie counting theorem and several arithmetic conjectures. Our methods are inspired by previous applications of the Pila-Zannier method and, in particular, the recent proof by Habegger and Pila of the Zilber-Pink conjecture for curves in abelian varieties. This is joint work with Christopher Daw. The second part is devoted to a Galois cohomological result towards the proof of the Zilber-Pink conjecture. Let G be a linear algebraic group over a field k of characteristic 0. We show that any two connected semisimple k-subgroups of G that are conjugate over an algebraic closure of kare actually conjugate over a finite field extension of k of degree bounded independently of the subgroups. Moreover, if k is a real number field, we show that any two connected semisimple k-subgroups of G that are conjugate over the field of real numbers ℝ are actually conjugate over a finite real extension of k of degree bounded independently of the subgroups. This is joint work with Mikhail Borovoi and Christopher Daw. Finally, in the third part, we consider the distribution of compact Shimura varieties. We recall that a Shimura variety S of dimension 1 is always compact unless S is a modular curve. We generalize this observation by defining a height function in the space of Shimura varieties attached to a fixed real reductive group. In the case of unitary groups, we prove that the density of non-compact Shimura varieties is zero.
19

Les constructions causatives du français et du chinois / The causative constructions in french and in chinese

Hu, Xiaoshi 19 October 2017 (has links)
Cette thèse est centrée autour des problèmes concernant les constructions causatives du français et du chinois, elle se veut une contribution empirique et théorique à l’étude formelle des systèmes verbaux du français et du chinois. Il sera montré que la défectivité en traits des têtes de phases joue un rôle important motivant la formation des constructions au sein de ces deux langues. Concernant la construction causative en faire du francais, nous allons utiliser l’interprétation de respectivement comme test pour justifier son statut bi-propositionnel? et l’examen des relations quantificationnelles va montrer que le vP causativisé dans le complément de faire constitue une phase défective, sélectionnée par une autre tête fonctionnelle phasale. De plus, la défectivité du vP causativisé et les traits-phi intégrés aux clitiques donnent lieu aux distributions des différents clitiques. A la différence de la construction causative du francais qui implique un TP défectif dans une structure bi-propositionnelle, les verbes causatifs du chinois sélectionnent directement un v*P phasal et il n’y a plus de projection fonctionnelle intervenante. Il sera montré que le chinois fait aussi la distinction entre les Temps fini et infinitif, bien qu’une telle distinction ne se manifeste pas sur les formes morphologiques des verbes. Cette thèse va aussi examiner la corrélation entre les verbes rang/jiao/gei, nous allons montrer que leurs fonctions causative et passive désignent différentes structures argumentales, et il n’y a pas de relation dérivationnelle entre ces deux structures argumentales de ces verbes. En ce qui concerne la perspective théorique, il sera montré qu’il y a quatre structures phasales possibles correspondantes à de différentes structures argumentales des verbes causatifs du francais et du chinois? et cette thèse va aussi explorer la pertinence de la condition d’impénétrabilité de phase et de la condition de minimalité par rapport aux différentes opérations de la syntaxe étroite. / This dissertation concentrates on the problems concerning the causative constructions in French and in Chinese, it constitutes empirical and theoretical contributions to the formal study of French and Chinese verbal systems. It will be shown that the feature defectivity of phasal heads plays a key role motivating the formation of constructions in the two languages. Concerning the causative construction of faire in French, we will use the interpretation of Respectively as test to justify its bi-clausal status; and the exploration of the quantificational relations will show that the causativized vP in the complement of faire determines a defective phase, selected by another phasal functional head. In addition, the defectivity of the causativized vP and the phi-features integrated in the clitics result in the distribution of different types of clitics. Different from the causative construction in French involving a defective TP in a bi-clausal structure, Chinese causative verbs sub-categorize directly a phasal causativized v*P, and there is no other intervening phasal projections. It will be shown that Chinese distinguishes finite and infinitive Tenses as well, even such a distinction may not be manifested on verb forms. Concerning the verbs rang/jiao/gei in Chinese, we will show that their causative and passive functions carry out the different argument structures; and there is no derivational relation between the two argument structures of these verbs. Concerning the theoretic perspective, it will be shown that there are four phasal structures corresponding to the different argument structures of the causative verbs in French and in Chinese. In addition, this thesis will also explore the performance of the phase impenetrability condition and of the minimality condition with respect on different operations of the narrow syntax.
20

[pt] DINÂMICAS MINIMAIS EM CONJUNTOS DE CANTOR E DIAGRAMAS DE BRATTELI / [en] MINIMAL DYNAMICS ON CANTOR SETS AND BRATTELI DIAGRAMS

CAMILA SOBRINHO CRISPIM 16 June 2021 (has links)
[pt] Um diagrama de Bratteli B é um objeto combinatório representado por um grafo dividido em infinitos níveis, cada um com número finito de vértices e de arestas entre vértices de níveis consecutivos. Além disso, todo vértice possui ligação com vértices dos níveis precedente e sucessor. Estudamos, do ponto de vista topológico, o espaço dos caminhos infinitos formados pelas arestas de um diagrama de Bratteli, denotado por XB. Estabelecemos uma relação de equivalência neste espaço, denominada AF. Quando é possível definir uma ordem parcial em XB o diagrama é dito ordenado; neste caso, definimos um homeomorfismo em XB denominado de função de Bratteli-Vershik. Consideramos sistemas dinâmicos minimais definidos em conjuntos de Cantor e associamos a estes diagramas de Bratteli ordenados. Um exemplo paradigmático de um conjunto de Cantor é o espaço das sequências infinitas formadas por 00s e 10s, munido de uma métrica apropriada. Neste espaço são definidas as funções odômetro. Definimos a relação de equivalência orbital, na qual duas sequências são equivalentes se estão na mesma órbita do odômetro, e a relação de equivalência de caudas, onde duas sequências são equivalentes se a partir de alguma entrada elas são iguais. Estudamos como estas duas relações estão relacionadas. Provamos que o odômetro diádico é um homeomorfismo minimal definido em um conjunto de Cantor e, portanto, pode ser associado a um diagrama de Bratteli ordenado. Uma relação de equivalência é dita étale quando admite uma topologia gerada por uma ação local. Dois exemplos são as relações AF e orbital. Dada uma relação de equivalência étale R em um espaço X, definimos um invariante algébrico D(X,R). Construímos o grupo de dimensão de um diagrama de Bratteli. Provamos, então, que dado um diagrama de Bratteli B, seu grupo de dimensão é isomorfo a D(XB,RB), onde RB é relação AF de B. Finalmente, estudamos sob quais condições um grupo abeliano ordenado é o grupo de dimensão de um diagrama de Bratteli. Esta dissertação é baseada no livro de Ian F. Putnam Cantor minimal systems, publicado em University Lecture Series, 70. American Mathematical Society, Providence, RI, 2018. [6]. / [en] A Bratteli diagram B is a combinatorial object represented by a graph divided into infinite levels, each level with a finite number of vertices and edges between vertices of consecutive levels. Moreover, every vertex is connected to vertices of the preceding and successor levels. We study, from a topological point of view, the space of infinite paths formed by the edges of a Bratteli diagram, denoted by XB. We establish an equivalence relation on this space, called the AF relation. When it is possible to define a partial order in XB the Bratteli diagram is called ordered; in this case, we define a homeomorphism on XB called the Bratteli-Vershik function. We consider minimal dynamic systems defined on Cantor sets and associate to these systems ordered Bratteli diagrams. A paradigmatic example of a Cantor set is the space of the infinite sequences formed by 00s and 10s, equipped with an appropriate metric. In this space, are defined the odometer functions. We define the orbital equivalence relation, in which two elements of the Cantor set are equivalent if they are in the same orbit of the odometer, and the tail equivalence relation, where two sequences are equivalents if they differ in only finitely many entries. We study how these equivalence relations are related. We prove that the dyadic odometer is a minimal homeomorphism and, therefore, it can be associated to a ordered Bratteli diagram. An equivalence relation is called étale if it admits a topology generated by a local action. Two examples are the AF equivalence relation and the orbital equivalence relation above. Given an étale equivalence relation R on a space X, we define an algebraic invariant D(X,R). We construct the dimension group of a Bratteli diagram. Then, we prove that given a Bratteli diagram B, its dimension group is isomorphic to D(XB,RB), where RB is the AF equivalence relation of B. Finally, we study under which conditions an ordered abelian group is the dimension group for some Bratteli diagram. This master thesis is based on the book by Ian F. Putnam Cantor minimal systems, published in University Lecture Series, 70. American Mathematical Society, Providence, RI, 2018. [6].

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