Dissertations / Theses on the topic 'C*-algebra'
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Thom, Andreas Berthold. "Connective E-theory and bivariant homology for C*-algebras." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=968501311.
Full textMelo, S. T., R. Nest, and Elmar Schrohe. "C*-structure and K-theory of Boutet de Monvel's algebra." Universität Potsdam, 2001. http://opus.kobv.de/ubp/volltexte/2008/2616/.
Full textRankin, Fenella Kathleen Clare. "The arithmetic and algebra of Luca Pacioli (c.1445-1517)." Thesis, University of London, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338276.
Full textErnst, Dana C. "A diagrammatic representation of an affine C Temperley-Lieb algebra." Connect to online resource, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3315838.
Full textGrundling, Hendrik, and hendrik@maths unsw edu au. "Host Algebras." ESI preprints, 2000. ftp://ftp.esi.ac.at/pub/Preprints/esi896.ps.
Full textGupta, Davender Nath. "Expressing imaging algorithms using a C++ based image algebra programming environment /." Online version of thesis, 1990. http://hdl.handle.net/1850/11370.
Full textDitsche, Jochen. "Pseudodifferential analysis in Y*-algebras [psi*-algebras] on transmission spaces, infinite solving ideal chains and K-theory for conformally compact spaces." Aachen Shaker, 2008. http://d-nb.info/988688409/04.
Full textAl-Rawashdeh, Ahmed. "The unitary group as an invariant of a simple unital C*-algebra." Thesis, University of Ottawa (Canada), 2003. http://hdl.handle.net/10393/28972.
Full textOliveira, Everton Franco de. "Produto cruzado de uma C*-álgebra por Z, generalização do teorema de Fejér e exemplos." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/45/45131/tde-08032016-182415/.
Full textWe present an introduction to C * -algebras and the construction of the crossed product $A times_{\\alpha} Z$, where A is a C *-algebra with unit, and $\\alpha$ is an automorphism in A. We also study a generalization of Fejérs theorem on crossed product context. As an example of crossed product, we prove that $C times_ Z$ is isomorphic to C(S^1). Let X be a compactification of Z by addition of the symbols $+\\infty$ and $-\\infty$. We prove that $C(X) times_{\\alpha} Z$ is isomorphic A, the closure of set of classics pseudo-differential operators of order 0 on S^1, where is defined by a shift. Based on these isomorphisms, we see the implication of the generalization of Fejérs theorem for C(S^1) and A.
Wood, Peter John, and drwoood@gmail com. "Wavelets and C*-algebras." Flinders University. Informatics and Engineering, 2003. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20070619.120926.
Full textZaki, Adel Mohamed. "Ideal structure and state spaces of operator algebras." Thesis, University of Aberdeen, 1987. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU498573.
Full textMANARA, ELIA. "Multiplicative representations of surface groups." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2018. http://hdl.handle.net/10281/199017.
Full textA surface group is (isomorphic to) the fundamental group of a closed orientable surface of genus k greater or equal than 2. It is a small cancellation group (hence hyperbolic); its Cayley graph is isomorphic to a tiling of the hyperbolic plane by 2k-gons. One can define certain subsets of the Cayley graph called cones. The group acts on the set of cones with finitely many orbits, called cone types. A multiplicative representation of a surface group is a unitary representation defined on the Hilbert space of multiplicative functions. A multiplicative function on a surface group is a vector-valued function defined through the choice of a set of parameters, called matrix system. Two multiplicative functions are equivalent if they differ only on finitely many elements. An inner product can be defined for equivalence classes of multiplicative functions. We prove that at least for the case of a surface group of genus 2 and a choice of the matrices as non-negative scalars the inner product is not identically zero; thus, since it does not depend on the representatives for the multiplicative functions, it is well posed. This proof relies on the irreducibility of a certain matrix associated with the geometry of the Cayley graph; in particular, a certain Perron-Frobenius eigenvalue must be simple. A multiplicative representation then simply acts by left translation on the Hilbert space completion of the space of multiplicative functions with respect to the inner product above mentioned. The representation thus defined is tempered: we show that the matrix coefficients of the regular representation approximate those of the multiplicative representation. By the term boundary representation, we mean a representation of a certain crossed product C*-algebra, obtained by the action of the surface group on the C*-algebra of continuous functions on its boundary – which is homeomorphic to the unit circle. Such a boundary representation is given by a unitary representation of the group and a representation of the C*-algebra satisfying a covariance condition. We define a family of subspaces (indexed by a real quantity) of a space of vector-valued square integrable functions on the group and we act on these subspaces by left translation with the group and by multiplication with continuous functions on the compactification of the surface group (the group united with its boundary). Thus, we get some representations of the group and the algebra satisfying covariance and we show that the family has a limit for a subsequence of the indexes tending to zero. We then show that the action of the C*-algebra involves only the values of the functions on the boundary. Hence, we get a boundary representation. We show, moreover, that the limit thus obtained does not depend on the subsequence tending to zero. Hence, we get a well-defined representation of the crossed product C*-algebra. We show that the unitary part of this boundary representation is equivalent to the multiplicative representation: in fact, their functions of positive type coincide. Finally, we show that the boundary representation is irreducible. This result is achieved by exploiting the uniqueness (up to scaling) of the Perron-Frobenius eigenvalue obtained in the proof of the well-posedness of the inner product: in fact, we show that any projection intertwining both the group representation and the algebra representation allows to define an eigenvector of the same matrix corresponding to the Perron-Frobenius eigenvalue. Thus, after some calculations, we get that the projection considered must be trivial. By a version of Schur’s Lemma, this yields the irreducibility of the crossed product representation.
Armstrong, Becky. "Simplicity of twisted C*-algebras of topological higher-rank graphs." Thesis, The University of Sydney, 2019. http://hdl.handle.net/2123/20972.
Full textOerder, Kyle. "Operator algebras and quantum information." Diss., University of Pretoria, 2020. http://hdl.handle.net/2263/75515.
Full textDissertation (MSc)--University of Pretoria, 2020.
Physics
MSc
Unrestricted
Olivera, Marcela Irene Merklen. "Resultados motivados por uma caracterização de operadores pseudo-diferenciais conjecturada por Rieffel." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/45/45131/tde-04092003-154149/.
Full textWe work with functions defined on Rn with values in a C*-algebra A. We consider the set SA(Rn) of Schwartz functions (rapidly decreasing), with norm given by ||f||2 = ||?f(x)*f(x)dx||½ . We denote CB?(R2n,A) the set of functions which are C? and have all their derivatives bounded. We prove that pseudo-differential operators with symbol in CB?(R2n,A) are continuous on SA(Rn) with the norm || · ||2, thus generalizing the result in [10]. Rieffel proves in [1] that CB?(Rn,A) acts on SA(Rn) through a deformed product induced by an anti-symmetric matrix, J, as follows: LFg(x)=F×Jg(x) = ?e2?iuvF(x+Ju)g(x+v)dudv (an oscillatory integral). We say that an operator S is Heisenberg-smooth if the maps z |-> T-zSTz and ? |-> M-?SM?, z,? E Rn are C?; where Tzg(x)=g(x-z) and where M?g(x)=ei?xg(x). At the end of chapter 4 of [1], Rieffel proposes a conjecture: that all adjointable operators in SA(Rn) that are Heisenberg-smooth and that commute with the right-regular representation of CB?(Rn,A), RGf = f×JG, are operators of type LF . We proved this result for the case A = |C in [14], using Cordes\' characterization of Heisenberg-smooth operators on L2(Rn) as being the pseudo-differential operators with symbol in CB?(R2n). It is also proved in this thesis that, if a natural generalization of Cordes\' characterization is valid, then the Rieffel conjecture is true.
Iastremski, Priscilla. "O produto cruzado de uma C*-álgebra por um endomorfismo e a álgebra de Cuntz-Krieger." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/45/45131/tde-15052011-173459/.
Full textGiven A a C*-algebra with unit and \\alpha an *-endomorphism of A, a transfer operator for the pair (A, \\alpha) is a continuous positive linear map L: A --> A such that L(\\alpha(a)b) = a L(b), for all a, b \\in A. Under these conditions , we denote by T(A, \\alpha, L) the universal C*-algebra with unit generated by A and an element S subject to the relations Sa = \\alpha(a)S and S*aS = L(a). A redundancy is defined as a pair (a, k) \\in A x \\overline{ASS* A} such that abS = akS, for all b \\in A. In tjis work we define the C*-algebra called crossed-product as the quotient of T(A, \\alpha, L) by the closed two-sided ideal I generated by the set of all differences a-k, for all redundancies (a, k) such that a \\in \\overline, where by R we mean Im \\alpha. We prove that when \\alpha is injective with an hereditary range, then the crossed-product is isomorphic to the universal C*-algebra with unit, which we denote by U(A, \\alpha), generated by A and an isometry T subject to the relation \\alpha(a) = TaT*, for all a \\in A. We also prove that the Cuntz-Krieger algebra O_A can be characterized as the crossed-product we define in this work.
Mecklenburg, Trinity. "Elliptic Curves." CSUSB ScholarWorks, 2015. https://scholarworks.lib.csusb.edu/etd/186.
Full textBosa, Puigredon Joan. "Continuous fields of c-algebras, their cuntz semigroup and the geometry of dimension fuctions." Doctoral thesis, Universitat Autònoma de Barcelona, 2013. http://hdl.handle.net/10803/126516.
Full textThis thesis deals with C*-algebras and their K-theoretical invariants. We have mainly focused on the structure of a class of C*-algebras called continuous fields, and the study of one of its invariants, the Cuntz semigroup. More concretely, we analyse the following: (1)-Structure of Continuous Fields of C*-algebras : In the literature there are two examples which clearly give an idea about the complexity of continuous field C*-algebras. The first one was constructed by M. Dadarlat and G. A. Elliott in 2007, and it is a continuous field C*- algebra A over the unit interval with mutually isomorphic fibers, with non-finitely generated K-theory and such that it is nowhere locally trivial. The second example shows that, even if the K-theory of the fibers vanish, the field can be nowhere locally trivial if the base space is infinite-dimensional (Dadarlat, 2009). From the above examples, it is natural to ask which is the structure of continuous fields of Kirchberg algebras over a finite-dimensional space with mutually isomorphic fibers and finitely generated K-theory. This question has been adressed in Chapter 2 of the memoir. (2)-The Cuntz semigroup of continuous field C*-algebras : For commutative C*-algebras of lower dimension where there are no cohomological obstructions, a description of their Cuntz semigroup via point evaluation has been obtained in terms of (extended) integer valued lower semicontinuous functions on their spectrum (Robert, 2009). For more general continuous fields, the key is to describe the map : Cu(A) ! Q x2X Cu(Ax) given by hai = (ha(x)i)x2X; where Cu(Ax) is the Cuntz semigroup of the fiber Ax. In Chapter 3 of the memoir, the map is studied in the case when X has low dimension and all the fibers of the C(X)-algebra A are not necessarily mutually isomorphic. Concretely, we prove that it is possible to recover the Cuntz semigroup of a suitable class of continuous fields as the semigroup of global sections of tx2XCu(Ax) to X. This is further used to rephrase a classification result by Dadarlat, Elliott and Niu (2012) by using a single invariant instead of a sheaf of groups. (3)-Dimension Functions on a C*-algebra : The study of dimension functions on C -algebras was started by Cuntz in 1978, and further developed by B. Blackadar and D. Handelman in 1982. In the latter article, two natural questions arised: to decide whether the affine space of dimension functions is a simplex, and also whether the set of lower semicontinuous dimension functions is dense in the space of all dimension functions. In Chapter 4 we compute the stable rank of some class of continuous field C*-algebras, which helps us to move on to show that the above two conjectures have affirmative answers for continuous fields A over one-dimensional spaces and with mild assumptions on their fibers.
Berni, Jean Cerqueira. "Some algebraic and logical aspects of C∞-Rings." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/45/45131/tde-14022019-203839/.
Full textConforme observado por I. Moerdijk e G. Reyes em [63], os anéis C∞ têm sido estudados especialmente tendo em vista suas aplicações em Teoria de Singularidades e para construir toposes que sirvam de modelos para a Geometria Diferencial Sintética. Neste trabalho, seguimos um caminho complementar, aprofundando nosso conhecimento sobre eles por um viés mais puro, fazendo uso da Teoria das Categorias e os analisando a partir de pontos de vista algébrico e lógico-categorial. Iniciamos o trabalho apresentando uma sistematização abrangente dos fatos fundamentais da teoria (equacional) dos anéis C∞, distribuídos aqui e ali na literatura atual - a maioria sem demonstrações - mas que servem de base para a teoria. Na sequência, desenvolvemos alguns tópicos do que denominamos Álgebra Comutativa C∞, expandindo resultados parciais de [66] e [67]. Realizamos um estudo sistemático dos anéis C∞ von Neumann-regulares - na linha do estudo algébrico realizado em [2]- e apresentamos alguns resultados interessantes a seu respeito, juntamente com sua relação (funtorial) com os espaços booleanos. Estudamos algumas noções pertinentes à Teoria de Feixes para anéis ∞, tais como espaços (localmente) ∞anelados e o sítio de Zariski liso. Finalmente, descrevemos toposes classicantes para a teoria (algébrica) dos anéis C∞, a teoria (coerente) dos anéis locais C∞ e a teoria (algébrica) dos anéis C∞ von Neumann regulares.
Machálek, Lukáš. "Aplikace geometrických algeber." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-445454.
Full textGünther, Janne-Kathrin. "The C*-algebras of certain Lie groups." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0118/document.
Full textIn this doctoral thesis, the C*-algebras of the connected real two-step nilpotent Lie groups and the Lie group SL(2,R) are characterized. Furthermore, as a preparation for an analysis of its C*-algebra, the topology of the spectrum of the semidirect product U(n) x H_n is described, where H_n denotes the Heisenberg Lie group and U(n) the unitary group acting by automorphisms on H_n. For the determination of the group C*-algebras, the operator valued Fourier transform is used in order to map the respective C*-algebra into the algebra of all bounded operator fields over its spectrum. One has to find the conditions that are satisfied by the image of this C*-algebra under the Fourier transform and the aim is to characterize it through these conditions. In the present thesis, it is proved that both the C*-algebras of the connected real two-step nilpotent Lie groups and the C*-algebra of SL(2,R) fulfill the same conditions, namely the “norm controlled dual limit” conditions. Thereby, these C*-algebras are described in this work and the “norm controlled dual limit” conditions are explicitly computed in both cases. The methods used for the two-step nilpotent Lie groups and the group SL(2,R) are completely different from each other. For the two-step nilpotent Lie groups, one regards their coadjoint orbits and uses the Kirillov theory, while for the group SL(2,R) one can accomplish the calculations more directly
Martini, Alessio. "Algebras of differential operators on Lie groups and spectral multipliers." Doctoral thesis, Scuola Normale Superiore, 2010. http://hdl.handle.net/11384/85663.
Full textBouvier, Patrick. "Contributions à l’étude de l’effet Hawking pour des modèles en interaction." Thesis, Paris 11, 2013. http://www.theses.fr/2013PA112356/document.
Full textThe Hawking effect predicts that, in a space- time describing the collapse of a spherically symmetric star to a Schwarzschild black hole, a static observer at infinity sees the Unruh state as a thermal state at Hawking temperature. The first mathematical proof of the Hawking effect, in the original setting of Hawking, is due to Bachelot. His work on Klein-Gordon fields has been extended to Dirac fields, in the first place by Bachelot himself, and by Melnyk after that. Those works, placed in the setup of a spherically symmetric star, have been completed by Häfner, who gave a rigorous proof of the Hawking effect for Dirac fields, outside a star collapsing to a Kerr black hole. The aim of this thesis is to study the Hawking effect not for a model of free quantum fields, in which case the problems can be reduced to studies on linear partial differential equations, but for a model of interacting Dirac fields. The interaction will be considered as a static, compactly-supported interaction, living outside the star. We choose to study a toy model in a 1+1 dimensional space-time. Using the fact that the problem is spherically symetric, one can, at least in the free case, reduce the real problem to this toy model. We study the behavior of Dirac fermions fields in various situations : first, for an observable following the star's collapse ; then, for a static observable ; finally, for a time-dependent interaction, fixed close to the star's boundary. In each of those cases, we show the existence of the Hawking Effect and give the corresponding limit state
Günther, Janne-Kathrin. "The C*-algebras of certain Lie groups." Electronic Thesis or Diss., Université de Lorraine, 2016. http://www.theses.fr/2016LORR0118.
Full textIn this doctoral thesis, the C*-algebras of the connected real two-step nilpotent Lie groups and the Lie group SL(2,R) are characterized. Furthermore, as a preparation for an analysis of its C*-algebra, the topology of the spectrum of the semidirect product U(n) x H_n is described, where H_n denotes the Heisenberg Lie group and U(n) the unitary group acting by automorphisms on H_n. For the determination of the group C*-algebras, the operator valued Fourier transform is used in order to map the respective C*-algebra into the algebra of all bounded operator fields over its spectrum. One has to find the conditions that are satisfied by the image of this C*-algebra under the Fourier transform and the aim is to characterize it through these conditions. In the present thesis, it is proved that both the C*-algebras of the connected real two-step nilpotent Lie groups and the C*-algebra of SL(2,R) fulfill the same conditions, namely the “norm controlled dual limit” conditions. Thereby, these C*-algebras are described in this work and the “norm controlled dual limit” conditions are explicitly computed in both cases. The methods used for the two-step nilpotent Lie groups and the group SL(2,R) are completely different from each other. For the two-step nilpotent Lie groups, one regards their coadjoint orbits and uses the Kirillov theory, while for the group SL(2,R) one can accomplish the calculations more directly
Roman, Ahmed Hemdan. "Zero Divisors and Linear Independence of Translates." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/53956.
Full textMaster of Science
Masliah, Ian. "Méthodes de génération automatique de code appliquées à l’algèbre linéaire numérique dans le calcul haute performance." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS285/document.
Full textParallelism in today's computer architectures is ubiquitous whether it be in supercomputers, workstations or on portable devices such as smartphones. Exploiting efficiently these systems for a specific application requires a multidisciplinary effort that concerns Domain Specific Languages (DSL), code generation and optimization techniques and application-specific numerical algorithms. In this PhD thesis, we present a method of high level programming that takes into account the features of heterogenous architectures and the properties of matrices to build a generic dense linear algebra solver. Our programming model supports both implicit or explicit data transfers to and from General-Purpose Graphics Processing Units (GPGPU) and Integrated Graphic Processors (IGPs). As GPUs have become an asset in high performance computing, incorporating their use in general solvers is an important issue. Recent architectures such as IGPs also require further knowledge to program them efficiently. Our methodology aims at simplifying the development on parallel architectures through the use of high level programming techniques. As an example, we developed a least-squares solver based on semi-normal equations in mixed precision that cannot be found in current libraries. This solver achieves similar performance as other mixed-precision algorithms. We extend our approach to a new multistage programming model that alleviates the interoperability problems between the CPU and GPU programming models. Our multistage approach is used to automatically generate GPU code for CPU-based element-wise expressions and parallel skeletons while allowing for type-safe program generation. We illustrate that this work can be applied to recent architectures and algorithms. The resulting code has been incorporated into a C++ library called NT2. Finally, we investigate how to apply high level programming techniques to batched computations and tensor contractions. We start by explaining how to design a simple data container using modern C++14 programming techniques. Then, we study the issues around batched computations, memory locality and code vectorization to implement a highly optimized matrix-matrix product for small sizes using SIMD instructions. By combining a high level programming approach and advanced parallel programming techniques, we show that we can outperform state of the art numerical libraries
Mendoza, Quispe Wilfredo. "K-teoría de C*-álgebras." Master's thesis, Universidad Nacional Mayor de San Marcos, 2014. https://hdl.handle.net/20.500.12672/3780.
Full textTesis
Ortiz, Marby Zuley Bolaños. "Componentes conexas de grupos em teorias NIP." Universidade Federal de Goiás, 2017. http://repositorio.bc.ufg.br/tede/handle/tede/7089.
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In this work, we estudied three special subgroups of bounded index in G: The intersection of subgroups definables of G, the small type-definable subgroup and the small invariant subgroup of G, called connected components of G and denoted G0G00 e G¥. We give an exposition of theorem of Gismatullim, where he proved the existence of G¥ in a theory with NIP.
Neste trabalho estudamos três subgrupos de um grupo G com índices limitados em G: A interseção de todos os subgrupos definíveis de G , o menor subgrupo tipo-definível e o menor subgrupo invariante de G, chamados componentes conexas de G, denotados respectivamente G0G00 e G¥. Apresentamos uma demonstração da existência de G¥ em uma teoria NIP, baseados na prova feita por Gismatullin em 2011.
Dutra, Allysson Gomes. "Ideais primitivos de C*-álgebras." Florianópolis, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/100802.
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Começamos este trabalho definindo alguns conceitos preliminares em C*-álgebras, onde abordamos o teorema de Gelfand, que trata de representar cada C*-álgebra abeliana A por C_0(?(A))), onde $?(A)$ (caracteres) é um espaço Hausdorff localmente compacto. Num segundo momento trabalhamos o conceito de representação de C*-álgebras, onde o caso particular das representações irredutíveis tem papel análogo ao dos caracteres no caso abeliano, os núcleos de tais representações formam o espaço dos ideais primitivos Prim(A). Quando nos restringimos ás C*-álgebras separáveis o espaço Prim(A) possui a propriedade de Baire, propriedade esta que é importante para se concluir a equivalência entre os conceitos de ideal primo fechado e ideal primitivo, e desta equivalência decorre a sobriedade de Prim(A). Na parte final do trabalho estudamos o importante teorema de Dauns-Hofmann, que nos deu suporte para a demonstração do isomorfismo de Dixmier, e este último usamos para demonstrar o isomorfismo entre Z(A) e C_0(Prim(A)) no caso em que Prim(Ã) é Hausdorff.
We start this work defining some premilinary concepts in C*-algebras, where we discuss the Gelfand theorem, wich deals with the representation of each abelian C*-algebra A by C0(O(A)), where O (A) (characters) is a locally compact Hausdorff spaces. Subsequently, we focus on the concept of the C*-algebras representation, where the particular case of irreducible representations has similar role of the characters in the abelian case, the kernel of such representations form the space of primitives ideals Prim(A). When we are restricted to separables C*-algebras the Prim(A) space has the Baire property, wich is important to conclude the equivalence between the concepts of closed prime ideal and primitive ideal, and from this equivalence derives the sobriety of the Prim(A). In the last chapter, we study the important theorem of Dauns-Hofmann, which gave us support for the demonstration of the Dixmier isomorphism, and this last one we used to demonstrate the isomorphism between Z(A) and C0(Prim(A)) in the case where Prim(Ã) is Hausdorff.
Bár, Filip. "Infinitesimal models of algebraic theories." Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/267026.
Full textBiazotto, Soyara Carolina. "C*-Álgebras de grafos com linhas finitas." Florianópolis, SC, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/96333.
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Dado um grafo com linhas finitas E, vamos definir a C*-álgebra associada a E, que denotaremos por C*(E), como sendo a C*-álgebra universal gerada por uma E-família de Cuntz-Krieger. Através de um exemplo, mostraremos que a E-família de Cuntz-Krieger universal tem todos os elementos não nulos. Como a um grafo E podem existir muitas E-famílias de Cuntz-Krieger, e todas essas famílias geram C*-álgebras, vamos mostrar algumas condições suficientes para que estas C*-álgebras sejam isomorfas a C*(E). Também estudaremos a estrutura de ideais de C*(E).
Given a row-finite graph E, we are going to define the C.-algebra associated to E, which we denote by C.(E), as the universal C.-algebra generated by Cuntz-Krieger E-family. Through an example, we are going to show that the universal Cuntz-Krieger E-family has all the elements different from zero. Since there can be many Cuntz-Krieger family associated to a graph E, and all these families generate C.- algebras, we are going to show sufficient conditions so that they are be isomorphic to C.(E). We will also study the ideal structure of C.(E).
Male, Camille. "Forte et fausse libertés asymptotiques de grandes matrices aléatoires." Phd thesis, Ecole normale supérieure de lyon - ENS LYON, 2011. http://tel.archives-ouvertes.fr/tel-00673551.
Full textHupšil, Radim. "Rastrová analýza pro GIS nástroj ArcGIS." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2008. http://www.nusl.cz/ntk/nusl-235877.
Full textTaipe, Huisa Frank. "Quantum transformation groupoids : an algebraic and analytical approach." Thesis, Normandie, 2018. http://www.theses.fr/2018NORMC258.
Full textThis thesis is concerned with the construction of a family of quantum transformation groupoids in the algebraic framework in the form of the measured multiplier Hopf *-algebroids in the sense of Timmermann and Van Daele and also in the context of operator algebras in the form of Hopf C*-bimodules on a C*-base in the sense of Timmermann.In the purely algebraic context, we first give a definition of a braided commutative Yetter-Drinfeld *-algebra over an algebraic quantum group in the sense of Van Daele and a Yetter-Drinfeld integral on it. Then, using these objects we construct a measured multiplier Hopf *-algebroid, we call to this new object an algebraic quantum transformation groupoid.In order to pass to the operator algebra framework, we give some conditions on the Yetter-Drinfeld integral inspired by the properties of KMS-weights on C*-algebras which will allow us to use the Gelfand–Naimark–Segal construction to extend all the purely algebraic objects to the C*-algebraic level. At this level, we construct in a similar way to that used in the work of Enock and Timmermann, a new mathematical object that we call a C*-algebraic quantum transformation groupoid, which is defined using the language of Hopf C*-bimodules on C*-bases
DAL, VERME GIULIA. "C*-algebras associated to monoids and groupoids, and Bass-Serre theory for groupoids." Doctoral thesis, Università degli studi di Pavia, 2021. http://hdl.handle.net/11571/1431718.
Full textPerugini, Stefania. "Costruzione di Gruppi di Lie con tecniche di Equazioni Differenziali Ordinarie." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14698/.
Full textVala, Jiří. "Regulační soustavy." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2007. http://www.nusl.cz/ntk/nusl-412766.
Full textMarinho, Andr? Afonso Ara?jo. "Aplica??es da q-?lgebra em f?sica da mat?ria condensada." Universidade Federal do Rio Grande do Norte, 2014. http://repositorio.ufrn.br:8080/jspui/handle/123456789/16631.
Full textCoordena??o de Aperfei?oamento de Pessoal de N?vel Superior
We address the generalization of thermodynamic quantity q-deformed by q-algebra that describes a general algebra for bosons and fermions . The motivation for our study stems from an interest to strengthen our initial ideas, and a possible experimental application. On our journey, we met a generalization of the recently proposed formalism of the q-calculus, which is the application of a generalized sequence described by two parameters deformation positive real independent and q1 and q2, known for Fibonacci oscillators . We apply the wellknown problem of Landau diamagnetism immersed in a space D-dimensional, which still generates good discussions by its nature, and dependence with the number of dimensions D, enables us future extend its application to systems extra-dimensional, such as Modern Cosmology, Particle Physics and String Theory. We compare our results with some experimentally obtained performing major equity. We also use the formalism of the oscillators to Einstein and Debye solid, strengthening the interpretation of the q-deformation acting as a factor of disturbance or impurity in a given system, modifying the properties of the same. Our results show that the insertion of two parameters of disorder, allowed a wider range of adjustment , i.e., enabling change only the desired property, e.g., the thermal conductivity of a same element without the waste essence
Abordamos a generaliza??o das quantidades termodin?micas q-deformadas atrav?s da q-?lgebra que descreve uma ?lgebra generalizada para b?sons e f?rmions. A motiva??o para o nosso estudo surge do interesse de fortalecer nossas id?ias iniciais, a fim de propor uma poss?vel aplica??o experimental. Em nossa jornada, conhecemos uma generaliza??o recentemente proposta ao formalismo do q-c?lculo, que ? a aplica??o de uma seq??ncia generalizada, descrita por dois par?metros de deforma??o reais positivos e independentes q1 e q2, conhecidos por osciladores de Fibonacci. Aplicamos ao conhecido problema do diamagnetismo de Landau imerso em um espa?o D-dimensional, que ainda gera boas discuss?es por sua natureza, e a depend?ncia com o n?mero de dimens?es D, nos possibilita futuramente estendermos a sua aplica??o para sistemas extra-dimensionais, tais como a CosmologiaModerna, a F?sica de Part?culas e Teoria de Cordas. Comparamos nossos resultados com alguns obtidos experimentalmente, apresentando grande equival?ncia. Aplicamos ainda o formalismo dos osciladores aos s?lidos de Einstein e Debye, fortalecendo ? interpreta??o da q-deforma??o atuando como um fator de perturba??o ou impureza, num determinado sistema, modificando as propriedades do mesmo. Nossos resultados mostram que a inser??o de dois param?tros de desordem, possibilitaram uma maior faixa de ajuste, ou seja, possibilitando alterar apenas a propriedade desejada, por exemplo, a condutividade t?rmica de um elemento sem que o mesmo perca sua ess?ncia .
Ferreira, Davi Morais. "Integração de bibliotecas científicas de propósito especial em uma plataforma de componentes paralelos." reponame:Repositório Institucional da UFC, 2010. http://www.repositorio.ufc.br/handle/riufc/17757.
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The contribution of traditional scienti c libraries shows to be consolidated in the construction of high-performance applications. However, such an artifact of development possesses some limitations in integration, productivity in large-scale applications, and exibility for changes in the context of the problem. On the other hand, the development technology based on components recently proposed a viable alternative for the architecture of High-Performance Computing (HPC) applications, which has provided a means to overcome these challenges. Thus we see that the scienti c libraries and programming orientated at components are complementary techniques in the improvement of the development process of modern HPC applications. Accordingly, this work aims to propose a systematic method for the integration of scienti c libraries on a platform of parallel components, HPE (Hash Programming Environment), to o er additional advantageous aspects for the use of components and scienti c libraries to developers of parallel programs that implement high-performance applications. The purpose of this work goes beyond the construction of a simple encapsulation of the library in a component; it aims to provide the bene ts in integration, productivity in large-scale applications, and the exibility for changes in the context of a problem in the use of scienti c libraries. As a way to illustrate and validate the method, we have incorporated the libraries of linear systems solvers to HPE, electing three signi cant representatives: PETSc, Hypre, e SuperLU.
A contribuição das tradicionais bibliotecas cientí cas mostra-se consolidada na construção de aplicações de alto desempenho. No entanto, tal artefato de desenvolvimento possui algumas limitações de integração, de produtividade em aplicações de larga escala e de exibilidade para mudanças no contexto do problema. Por outro lado, a tecnologia de desenvolvimento baseada em componentes, recentemente proposta como alternativa viável para a arquitetura de aplicações de Computação de Alto Desempenho (CAD), tem fornecido meios para superar esses desa os. Vemos assim, que as bibliotecas cientí cas e a programação orientada a componentes são técnicas complementares na melhoria do processo de desenvolvimento de aplicações modernas de CAD. Dessa forma, este trabalho tem por objetivo propor um método sistemático para integração de bibliotecas cientí cas sobre a plataforma de componentes paralelos HPE (Hash Programming Environment ), buscando oferecer os aspectos vantajosos complementares do uso de componentes e de bibliotecas cientí cas aos desenvolvedores de programas paralelos que implementam aplicações de alto desempenho. A proposta deste trabalho vai além da construção de um simples encapsulamento da biblioteca em um componente, visa proporcionar ao uso das bibliotecas cientí cas os benefícios de integração, de produtividade em aplicações de larga escala e da exibilidade para mudanças no contexto do problema. Como forma de exempli car e validar o método, temos incorporado bibliotecas de resolução de sistemas lineares ao HPE, elegendo três representantes significativos: PETSc, Hypre e SuperLU.
Lewis, Elizabeth Faith. "Peter Guthrie Tait : new insights into aspects of his life and work : and associated topics in the history of mathematics." Thesis, University of St Andrews, 2015. http://hdl.handle.net/10023/6330.
Full textKo, Chun-Chieh, and 柯俊傑. "Two Characterizations of Commutativity for C*-algebra." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/18523063789752732824.
Full text國立中山大學
應用數學系研究所
90
In this thesis, We investigate the problem of when a C*-algebra is commutative through continuous functional calculus, The principal results are that: (1) A C*-algebra A is commutative if and only if e^(ix)e^(iy)=e^(iy)e^(ix), for all self-adjoint elements x,y in A. (2) A C*-algebra A is commutative if and only if e^(x)e^(y)=e^(y)e^(x) for all positive elements x,y in A. We will give an extension of (2) as follows: Let f:[a,b]-->[c,d] be any continuous strictly monotonic function where a,b,c,d in R, a
Allen, Stephen Douglas. "The categorical properties of higher rank graphs and applications to their C*-algebras." Thesis, 2010. http://hdl.handle.net/1959.13/807531.
Full textThe class of Cuntz-Krieger C*-algebras associated to higher rank graphs (k-graphs) represents an interesting field of study because of their similarities to the C*-algebras associated to directed graphs and also their dissimilarities which enable them to have much richer and complex structures. Here we develop some methods for determining Morita equivalence between k-graph algebras. Firstly, we define a C*-algebra generated by partial isometries, subject to some relations similar to the Cuntz-Krieger relations of a k-graph algebra. We then show that this C*algebra is isomorphic to a corner of a k-graph algebra. Since every k-graph algebra is trivially a corner of itself, then it follows that all k-graph algebras can be obtained this way. We show that this C*-algebra is universal and then prove an analogue of the Gauge Invariant Uniqueness Theorem for corners of k-graph algebras and then show a few applications of this theorem. Secondly, we define a way of generating a k-graph [C,d] from a category C and a functor δ : C → ℕk such that C is a full subcategory of [C,δ] and the degree map of [C,δ] is equal to d for any path that is the image of an element in C. This method is useful because it means one can define a k-graph from a category without needing to check if the factorisation property holds on that particular category. We then show some applications of generating a k-graph in this way. One application, in particular, is the k-graph analog of adding a tail to a directed graph. We also use this technique to generate some examples of the desingularisation of some k-graphs that are not row-finite.
Peebles, Jason Samuel. "Toeplitz C*-algebra of the semigroup of principal ideals in a number field." Thesis, 2007. http://hdl.handle.net/1828/2380.
Full text"Representing Certain Continued Fraction AF Algebras as C*-algebras of Categories of Paths and non-AF Groupoids." Doctoral diss., 2020. http://hdl.handle.net/2286/R.I.57148.
Full textDissertation/Thesis
Doctoral Dissertation Mathematics 2020
Petzka, Henning Hans. "Stably Non-stable C*-algebras with no Bounded Trace." Thesis, 2012. http://hdl.handle.net/1807/34845.
Full textWiart, Jaspar. "A characterization of faithful representations of the Toeplitz algebra of the ax+b-semigroup of a number ring." Thesis, 2013. http://hdl.handle.net/1828/4750.
Full textGraduate
0405
jaspar.wiart@gmail.com
Naarmann, Simon. "A Mayer-Vietoris Spectral Sequence for C*-Algebras and Coarse Geometry." Doctoral thesis, 2018. http://hdl.handle.net/11858/00-1735-0000-002E-E5FF-1.
Full textPennig, Ulrich. "Twisted K-theory with coefficients in a C*-algebra and obstructions against positive scalar curvature metrics." Doctoral thesis, 2009. http://hdl.handle.net/11858/00-1735-0000-0006-B3D2-7.
Full textPapish, Volodymyr Gregory. "The Hecke C*-algebra of the ax + b group of the Laurent series over a finite field." 2005. http://hdl.handle.net/1828/688.
Full textMaloney, Gregory. "Dimension Groups and C*-algebras Associated to Multidimensional Continued Fractions." Thesis, 2009. http://hdl.handle.net/1807/24315.
Full text