Dissertations / Theses on the topic 'Exterior algebra'

Thesis (Ph. D.)--University of Oregon, 2000.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 92-93). Also available for download via the World Wide Web; free to University of Oregon users.

In dieser Arbeit wird die de-Rham-Kohomologie für die Quantengruppen zu den vier klassischen Serien von Lie-Gruppen bestimmt und es wird der Hodgeschen Zerlegungssatz gezeigt. Als entscheidendes Mittel wurde der Laplace-Beltrami-Operator L für Woronowicz’ äußere Algebren entwickelt. Für transzendente Werte von q und reguläre Kalkülparameter z ist L diagonalisierbar. Für die obigen Quantengruppen bestimmen wir die Eigenwerte von L, die neben q und z von zwei integralen dominanten Gewichten abhängen. Wie im klassischen Fall wird die de-Rham-Kohomologie durch harmonische Formen repräsentiert. Jedoch entspricht nur im Fall der A-Serie jeder harmonischen Form auch eine de-Rham-Kohomologieklasse. Im Falle der B-, C- und D-Serien sind biinvariante Formen nicht notwendig geschlossen. Es gilt aber, dass jede biinvariante Form harmonisch ist. Das zweite Hauptresultat ist die Hodge-Zerlegung für die Quantengruppen GLq(N) und SLq(N): Ist der Kalkülparameter z regulär, so lässt sich jede Form eindeutig zerlegen in die Summe aus einem Rand, einem Korand und einem Kohomologierepräsentanten. Ferner gilt, analog zum klassischen Fall, dass die folgenden drei Formenräume übereinstimmen: die biinvarianten Formen, die harmonischen Formen und die de-Rham-Kohomologie. Für die orthogonalen und symplektischen Quantengruppen gibt es keine vollständige Hodge-Zerlegung. Nur für die Elemente, die im Bild des Laplace-Beltrami-Operators liegen, gibt es eine eindeutige Zerlegung in Rand und Korand. Für die Standardkalküle auf den Quantengruppen GLq(N) und SLq(N) wird die Größe von Woronowicz’ äußerer Algebra bestimmt. Es wird gezeigt, dass der Raum der linksinvarianten k-Formen (N² über k)-dimensional ist. Die Algebra der biinvarianten Formen ist graduiert kommutativ. Ihre Poincaré-Reihe ist (1+t)(1+t³) ... (1+t^(2N-1)). Biinvariante Formen sind geschlossen
Consider one of the standard bicovariant first order differential calculi for the quantum groups GLq(N), SLq(N), SOq(N), or SPq(N), where q is a transcendental complex number. It is shown that the de Rham cohomology of Woronowicz' external algebra coincides with the de Rham cohomologies of its left-invariant, its right-invariant and its bi-invariant subcomplexes. In the cases GLq(N) and SLq(N), the cohomology ring is isomorphic to the left-invariant external algebra and to the vector space of harmonic forms. We prove a Hodge decomposition theorem in these cases. The main technical tool is the spectral decomposition of the quantum Laplace-Beltrami operator. As in the classical case all three spaces of differential forms coincide: bi- invariant forms, harmonic forms and the de-Rham-cohomology. For orthog- onal and symplectic quantum groups there is no complete Hodge decompo- sition. In case of the standard calculi on the quantum groups GLq(N) and SLq(N), the size of exterior algebra is computed. The space of left-invariant k-forms has dimension C(N², k) (binomial coefficient). The algebra of bi-invariant forms is graded commutative with Poincaré series (1+t)(1+t³) ... (1+t^(2N-1)). Bi-invariant forms are closed

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
O complexo de Koszul é uma ferramenta de vital importância na Álgebra Comutativa. Ele nos permitirá definir alguns invariantes que nos dão informações refinadas acerca de um determinado módulo. Entre eles podemos ressaltar a profundidade e a multiplicidade de tal módulo em relação à um ideal. A primeira mede o comprimento da maior M-sequência formada por elementos do anel e a segunda nos dà informações assintóticas acerca do comprimento de módulos quocientes

We introduce the formalism of supersymmetric quantum mechanics, including super-symmetry charges,Z2-graded Hilbert spaces, the chirality operator and the Wittenindex. We show that there is a one to one correspondence of fermions and bosons forenergies different than zero, which implies that the Witten index measures the dif-ference of fermions and bosons at the ground state. We argue that the Witten indexis the index of an elliptic operator. Quantization of the supersymmetric non-linearsigma model shows that the Witten index equals the Euler characteristic of the un-derlying Riemannian manifold over which the theory is defined. Finally, the pathintegral representation of the Witten index is applied to derive the Gauss-Bonnettheorem. Apart from this we introduce elementary mathematical background in thesubjects of topological invariance, Riemannian manifolds and index theory
Vi introducucerar formalismen f ̈or supersymmetrisk kvantmekanik, d ̈aribland super-symmetryladdningar,Z2-graderade Hilbertrum, kiralitetsoperatorn och Wittenin-dexet. Vi visar att det r ̊ader en till en-korrespondens mellan fermioner och bosonervid energiniv ̊aer skillda fr ̊an noll, vilket medf ̈or att Wittenindexet m ̈ater skillnadeni antal fermioner och bosoner vid nolltillst ̊andet. Vi argumenterar f ̈or att Wittenin-dexet ̈ar indexet p ̊a en elliptisk operator. Kvantisering av den supersymmetriskaicke-linj ̈ara sigmamodellen visar att Wittenindexet ̈ar Eulerkarakteristiken f ̈or denunderliggande Riemannska m ̊angfald ̈over vilken teorin ̈ar definierad. Slutligenapplicerar vi v ̈agintegralrepresentationen av Wittenindexet f ̈or att h ̈arleda Gauss-Bonnets sats. Ut ̈over detta introduceras ocks ̊a grundl ̈aggande matematisk bakrundi ämnena topologisk invarians, Riemmanska m ̊angfalder och indexteori.

The aim of this thesis is to give a mathematical framework for scattering of electromagnetic waves by rough surfaces. We prove that the Maxwell transmission problem with a weakly Lipschitz interface,in finite energy norms, is well posed in Fredholm sense for real frequencies. Furthermore, we give precise conditions on the material constants ε, μ and σ and the frequency ω when this transmission problem is well posed. To solve the Maxwell transmission problem, we embed Maxwell’s equations in an elliptic Dirac equation. We develop a new boundary integral method to solve the Dirac transmission problem. This method uses a boundary integral operator, the rotation operator, which factorises the double layer potential operator. We prove spectral estimates for this rotation operator in finite energy norms using Hodge decompositions on weakly Lipschitz domains. To ensure that solutions to the Dirac transmission problem indeed solve Maxwell’s equations, we introduce an exterior/interior derivative operator acting in the trace space. By showing that this operator commutes with the two basic reflection operators, we are able to prove that the Maxwell transmission problem is well posed. We also prove well-posedness for a class of oblique Dirac transmission problems with a strongly Lipschitz interface, in the L_2 space on the interface. This is shown by employing the Rellich technique, which gives angular spectral estimates on the rotation operator.

En chimie quantique, les fonctions d'ondes électroniques peuvent être vues comme des multivecteurs ; les problèmes se traduisent par conséquent en langage mathématique grâce à l'algèbre extérieure.Nous rappelons en premier lieu certains résultats sur l'algèbre extérieure d'un espace de Hilbert concernant les produits extérieur et intérieur qui s'avèrent utiles pour la chimie quantique. Dans cette même partie, une méthode pour trouver l'idéal annulateur d'un multivecteur, correspondant en physique à l'espace d'exclusion par le principe de Pauli, est présentée et cette technique sera employée dans un chapitre ultérieur.Dans un deuxième temps, nous faisons un résumé des notions clés du formalisme quantique des systèmes fermioniques et de leur expression du point de vue de l'algèbre extérieure. Nous rappelons également les principales méthodes d'approximation basées sur les fonctions d'ondes en chimie quantique. Nous introduisons par la suite des versions généralisées des concepts de séniorité et d'ionicité. Ces nombres généralisés comptent de façon respective les couches partiellement et entièrement occupées pour toute partition en couches de l'espace des orbitales. Nous construisons ensuite les opérateurs hermitiens dont les espaces propres correspondent aux fonctions d'ondes associées aux différentes valeurs de séniorité généralisée ou d'ionicité généralisée. Les nombres de séniorité généralisée permettent d'établir des hiérarchies plus fines des espaces d'interaction de configuration à l'intérieur d'une séniorité ordinaire donnée.Dans le troisième et principal chapitre, nous présentons le cheminement qui nous a conduit à proposer un nouvel ansatz de fonctions d'ondes produits de géminales où les géminales ne sont pas fortement orthogonales mais satisfont à des contraintes géométriques plus faibles pour réduire l'effort de calcul sans sacrifier l'indiscernabilité des électrons. Nos contraintes géométriques se traduisent par des équations simples impliquant les traces de produits de matrices de géminales. Dans le modèle non trivial le plus basique, un ensemble de solutions est donné par des matrices diagonales par blocs où chaque bloc est de taille 2x2 et se compose d'une matrice de Pauli ou d'une matrice diagonale, multipliée par un paramètre complexe qui est à optimiser. Avec cet ansatz simplifié pour les géminales, le nombre de termes dans le calcul des éléments matriciels des observables quantiques, comme l'hamiltonien de l'équation de Schrödinger électronique, est considérablement réduit.Enfin, dans la dernière partie, nous explicitons la programmation de notre modèle de produits de géminales dans le code “Tonto”, qui est un programme et une librairie pour la cristallographie quantique et la chimie quantique écrits dans le langage “Foo”. La validité de notre code a été testée sur le calcul de l'énergie électronique de chaînes d'hydrogène. De plus, une preuve de principe que notre ansatz donne des résultats significativement plus précis que la méthode des géminales fortement orthogonales a été établie
In quantum chemistry, the electronic wave functions can be viewed as multivectors, therefore all problems translate into mathematical language thanks to the exterior algebra.We first recall some results related to the exterior and the interior products of the exterior algebra of a Hilbert space, which prove useful for quantum chemistry. We follow by presenting a method to find the annihilator ideal of a multivector, corresponding in physics to the excluded space by the Pauli principle, and this technique will be used in a later chapter.In a second step, we provide a summary of the key notions of the quantum formalism of fermionic systems and their counterpart from the point of view of the exterior algebra. We also recall the main approximation methods based on wave functions in quantum chemistry. We then introduce generalized versions of the concepts of seniority number and ionicity. These generalized numbers count respectively the partially occupied and fully occupied shells for any partition of the orbital space into shells. The Hermitian operators whose eigenspaces correspond to wave functions of definite generalized seniority or ionicity values are built. The generalized seniority numbers afford to establish refined hierarchies of configuration interaction spaces within those of fixed ordinary seniority.In the third and main chapter, we present the way that has led us to propose a new geminal product wave function ansatz where the geminals are not strongly orthogonal but satisfy weaker geometrical constraints to lower the computational effort without sacrificing the indistinguishability of the electrons. Our geometrical constraints translate into simple equations involving the traces of products of geminal matrices. In the simplest non-trivial model, a set of solutions is given by block-diagonal matrices where each block is of size 2x2 and consists of a Pauli matrix or a diagonal matrix, multiplied by a complex parameter to be optimized. With this simplified ansatz for geminals, the number of terms in the calculation of the matrix elements of quantum observables, like the Hamiltonian of the Schrödinger electronic equation, is considerably reduced.Finally, in the last part, we explain the implementation of our geminal product model in the computer code “Tonto”, which is a program and library for quantum crystallography and quantum chemistry written in the “Foo” language. The validity of our code has been tested on the calculation of the electronic energy of hydrogen chains. Moreover, a proof of principle that our ansatz gives significantly more accurate results than the strongly orthogonal geminal method has been established

Neste trabalho consideramos sistemas de equações lineares exíveis, sistemas de equações lineares cujos coe cientes têm incertezas de tipo o (:) ou O (:). Este tipo de incertezas irá ser analisado, à luz da análise não standard, como conjuntos de in nitesimais conhecidos como neutrizes. Em sistemas de equações lineares exíveis nem sempre existe uma solução exata. No entanto, neste trabalho apresentam-se condições que garantem a existência de pelo menos uma solução admissível, no sentido de inclusão, e as condições que garantem a existência de solução maximal nesse tipo de sistemas. Tais condições são restrições àcerca da ordem de grandeza do tipo de incertezas existentes, tanto na matriz dos coe cientes do sistema como na respetiva matriz dos termos independentes. Utilizando a regra de Cramer sob essas condições é possível produzir, pelo menos, uma solução admissível do sistema. No caso em que se garante a obtenção da solução maximal do sistema pela re- gra de Cramer, prova-se que essa solução corresponde à solução obtida pelo método de eliminação de Gauss; ABSTRACT: Systems of linear equations, called exible systems, with coe¢ cients having uncertain- ties of type o (:) or O (:) are studied from the point of view of nonstandard analysis. Then uncertainties of the afore-mentioned kind will be given in the form of so-called neutrices, for instance the set of all in nitesimals. In some cases an exact solution of a exible system may not exist. In this work conditions are presented that guarantee the existence of an admissible solution, in terms of inclusion, and also conditions that guarantee the existence of a maximal solution. These conditions concern restrictions on the size of the uncertainties appearing in the matrix of coe¢ cients and in the constant term vector of the system. Applying Cramer s rule under these conditions, one obtains, at least, an admis- sible solution of the system. In the case a maximal solution is produced by Cramer s rule, one proves that it is the same solution produced by Gauss-Jordan elimination.

O uso da geometria no dia a dia das pessoas tem importÃncia significativa por ser um assunto que utiliza desenhos, formas e teoremas como elementos de estudos para comprovar sua atuaÃÃo nos mais diversos campos da sociedade tais como engenharias, siderÃrgicas, arquiteturas, topografias, etc. Neste contexto, podemos afirmar que construÃÃes geomÃtricas propiciam a descoberta de valiosas ideias que auxiliam à compreensÃo das propriedades geomÃtricas. As avaliaÃÃes em larga escala apresentadas nos indicadores da educaÃÃo pÃblica no Estado do Cearà retratam claramente as dificuldades de aprendizagem por parte dos alunos quando relacionados aos conceitos geomÃtricos especificamente o teorema do Ãngulo externo tanto na teoria (conceito algÃbrico) como na prÃtica (conceito geomÃtrico). A partir desta analise, propomos realizar uma investigaÃÃo atravÃs da presente pesquisa que conseguisse identificar possÃveis entraves existentes no ensino de geometria para que pudesse obter avanÃos que visam melhorar no ensino relacionado ao Teorema do Ãngulo Externo e suas ConsequÃncias usando os ambientes de aprendizagens Velho Papel e Caneta (VPC) e o Ambiente virtual de Aprendizagem (AVA) com a operacionalidade do software educativo de geometria dinÃmica GeoGebra. O trabalho teve a participaÃÃo de um grupo de 12(doze) professores de matemÃtica em formaÃÃo continuada de um Curso de EspecializaÃÃo no Ensino de MatemÃtica da Universidade Vale do Acaraà (UVA) na cidade de Cascavel-Ce. O uso operacional e pedagÃgico do software de geometria dinÃmica GeoGebra foi aplicado em aulas expositivas com questionÃrios de problemas envolvendo o teorema do Ãngulo externo que busca avaliar o desempenho dos estudantes participantes da pesquisa em relaÃÃo suas prÃticas de sala de aula com o ensino de geometria. Adotamos abordagens qualitativa, exploratÃria e pesquisa-aÃÃo para caracterizar a pesquisa e buscamos tomar como base os pressupostos teÃricos e reflexivos segundo as concepÃÃes de Valente, Michele Artigue, Pais e Fiorentini e Lorenzato. A pesquisa revelou avanÃos no processo de aprendizagem dos estudantes participantes que se mostraram entusiasmados com os conhecimentos que construÃram e que os possibilitou estabelecerem um relacionamento colaborativo entre os grupos envolvidos (estudantes e professor-pesquisador)
The use of geometry in everyday life people have significant importance because it is a subject that uses designs, shapes and theorems as studies of evidence to make its activities in various fields of society such as engineering, steel, architecture, topography, etc. In this context, we can say that geometric constructions provide the discovery of valuable ideas that help the understanding of geometric properties. The large-scale assessments presented in public education indicators in the State of Ceara clearly portray the difficulties of learning by students when related to geometric concepts specifically the exterior angle theorem in theory (algebraic concept) and in practice (geometric concept). From this analysis, we propose to conduct an investigation through this research that could identify possible barriers in existing geometry teaching so he could obtain advances to improve the teaching related to the External Angle Theorem and its Consequences using the old learning environments and Paper pen (VPC) and the virtual Learning Environment (VLE) with the operation of educational software of dynamic geometry GeoGebra. The work was attended by a group of twelve (12) mathematics teachers in continuing education of a Specialization Course in Teaching of Mathematics at the University Vale do Acaraà (UVA) in the city of Cascavel-Ce. The operational and pedagogical use of dynamic geometry software GeoGebra was applied in lectures with questionnaires problems involving the exterior angle theorem that seeks to assess the performance of students participating in the survey regarding their classroom practices with the teaching of geometry. We adopted a qualitative, exploratory and action research approaches to characterize the research and seek to build on the theoretical and reflexive assumptions according to Valente conceptions, Michele Artigue, Parents and Fiorentini and Lorenzato. The survey showed progress in the learning process of participating students that were excited by the knowledge that built and that allowed establish a collaborative relationship between the groups involved (students and teacher-researcher).

Graded ideals over the polynomial ring are studied deeply with a huge of methods and results. Over the exterior algebra, there are not much known about the structures of minimal graded resolutions, Gröbner fans of graded ideals or the Koszul property of algebras defined by graded ideals. We study componentwise linearity, linear resolutions of graded ideals as well as universally, initially and strongly Koszul properties of graded algebras defined by a graded ideals over the exterior algebra. After that, we apply our results to Orlik-Solomon ideals of hyperplane arrangements and show in which way the exterior algebra is useful in the study of related combinatorial objects.

Diese Arbeit entwickelt aufbauend auf bekannten Resultaten die Modultheorie über der äußeren Algebra in Teilen weiter, insbesondere werden die Tiefe eines Moduls und Moduln mit linearer injektiver Auflösung untersucht. Angewendet werden die Resultate auf die Orlik-Solomon Algebra eines Matroids.

If E is an exterior algebra on a finite dimensional vector space and M is a graded E-module, the relationship between the resonance varieties of M and the minimal free resolution of M is studied. In the context of Orlik–Solomon algebras, we give a condition under which elements of the second resonance variety can be obtained. We show that the resonance varieties of a general M are invariant under taking syzygy modules up to a shift. As corollary, it is shown that certain points in the resonance varieties of M can be determined from minimal syzygies of a special form, and we define syzygetic resonance varieties to be the subvarieties consisting of such points. The (depth one) syzygetic resonance varieties of a square-free module M over E are shown to be subspace arrangements whose components correspond to graded shifts in the minimal free resolution of _SM, the square-free module over a commutative polynomial ring S corresponding to M. Using this, a lower bound for the graded Betti numbers of the square-free module M is given. As another application, it is shown that the minimality of certain syzygies of Orlik–Solomon algebras yield linear subspaces of their (syzygetic) resonance varieties and lower bounds for their graded Betti numbers.

In this paper, we prove the equality of the local arithmetic and analytic epsilon- and L-factors attached to the twisted exterior and symmetric square representations of GL(N). We will construct the twisted symmetric square local analytic gamma- and L-factor of GL(N) by applying Langlands-Shahidi method to odd GSpin groups. Then we reduce the problem to the stablity of local coefficients, and eventually prove the analytic stabitliy in this case by some analysis on the asymptotic behavior of certain partial Bessel functions.

In dieser Arbeit wird die de-Rham-Kohomologie für die Quantengruppen zu den vier klassischen Serien von Lie-Gruppen bestimmt und es wird der Hodgeschen Zerlegungssatz gezeigt. Als entscheidendes Mittel wurde der Laplace-Beltrami-Operator L für Woronowicz’ äußere Algebren entwickelt. Für transzendente Werte von q und reguläre Kalkülparameter z ist L diagonalisierbar. Für die obigen Quantengruppen bestimmen wir die Eigenwerte von L, die neben q und z von zwei integralen dominanten Gewichten abhängen. Wie im klassischen Fall wird die de-Rham-Kohomologie durch harmonische Formen repräsentiert. Jedoch entspricht nur im Fall der A-Serie jeder harmonischen Form auch eine de-Rham-Kohomologieklasse. Im Falle der B-, C- und D-Serien sind biinvariante Formen nicht notwendig geschlossen. Es gilt aber, dass jede biinvariante Form harmonisch ist. Das zweite Hauptresultat ist die Hodge-Zerlegung für die Quantengruppen GLq(N) und SLq(N): Ist der Kalkülparameter z regulär, so lässt sich jede Form eindeutig zerlegen in die Summe aus einem Rand, einem Korand und einem Kohomologierepräsentanten. Ferner gilt, analog zum klassischen Fall, dass die folgenden drei Formenräume übereinstimmen: die biinvarianten Formen, die harmonischen Formen und die de-Rham-Kohomologie. Für die orthogonalen und symplektischen Quantengruppen gibt es keine vollständige Hodge-Zerlegung. Nur für die Elemente, die im Bild des Laplace-Beltrami-Operators liegen, gibt es eine eindeutige Zerlegung in Rand und Korand. Für die Standardkalküle auf den Quantengruppen GLq(N) und SLq(N) wird die Größe von Woronowicz’ äußerer Algebra bestimmt. Es wird gezeigt, dass der Raum der linksinvarianten k-Formen (N² über k)-dimensional ist. Die Algebra der biinvarianten Formen ist graduiert kommutativ. Ihre Poincaré-Reihe ist (1+t)(1+t³) ... (1+t^(2N-1)). Biinvariante Formen sind geschlossen.
Consider one of the standard bicovariant first order differential calculi for the quantum groups GLq(N), SLq(N), SOq(N), or SPq(N), where q is a transcendental complex number. It is shown that the de Rham cohomology of Woronowicz'' external algebra coincides with the de Rham cohomologies of its left-invariant, its right-invariant and its bi-invariant subcomplexes. In the cases GLq(N) and SLq(N), the cohomology ring is isomorphic to the left-invariant external algebra and to the vector space of harmonic forms. We prove a Hodge decomposition theorem in these cases. The main technical tool is the spectral decomposition of the quantum Laplace-Beltrami operator. As in the classical case all three spaces of differential forms coincide: bi- invariant forms, harmonic forms and the de-Rham-cohomology. For orthog- onal and symplectic quantum groups there is no complete Hodge decompo- sition. In case of the standard calculi on the quantum groups GLq(N) and SLq(N), the size of exterior algebra is computed. The space of left-invariant k-forms has dimension C(N², k) (binomial coefficient). The algebra of bi-invariant forms is graded commutative with Poincaré series (1+t)(1+t³) ... (1+t^(2N-1)). Bi-invariant forms are closed.

The aim of this thesis is to give a mathematical framework for scattering of electromagnetic waves by rough surfaces. We prove that the Maxwell transmission problem with a weakly Lipschitz interface, in finite energy norms, is well posed in Fredholm sense for real frequencies. Furthermore, we give precise conditions on the material constants ε, μ and σ and the frequency ω when this transmission problem is well posed. To solve the Maxwell transmission problem, we embed Maxwell’s equations in an elliptic Dirac equation. We develop a new boundary integral method to solve the Dirac transmission problem. This method uses a boundary integral operator, the rotation operator, which factorises the double layer potential operator. We prove spectral estimates for this rotation operator in finite energy norms using Hodge decompositions on weakly Lipschitz domains. To ensure that solutions to the Dirac transmission problem indeed solve Maxwell’s equations, we introduce an exterior/interior derivative operator acting in the trace space. By showing that this operator commutes with the two basic reflection operators, we are able to prove that the Maxwell transmission problem is well posed. We also prove well-posedness for a class of oblique Dirac transmission problems with a strongly Lipschitz interface, in the L_2 space on the interface. This is shown by employing the Rellich technique, which gives angular spectral estimates on the rotation operator.

This thesis deals with cohomologies on the symplectic quotient of a Frölicher space which is locally diffeomorphic to a Euclidean Frölicher subspace of Rn of constant dimension equal to n. The symplectic reduction under consideration in this thesis is an extension of the Marsden-Weinstein quotient (also called, the reduced space) well-known from the finite-dimensional smooth manifold case. That is, starting with a proper and free action of a Frölicher-Lie-group on a locally Euclidean Frölicher space of finite constant dimension, we study the smooth structure and the topology induced on a small subspace of the orbit space. It is on this topological space that we will construct selected cohomologies such as : sheaf cohomology, Alexander-Spanier cohomology, singular cohomology, ~Cech cohomology and de Rham cohomology. Some natural questions that will be investigated are for instance: the impact of the symplectic structure on these di erent cohomologies; the cohomology that will give a good description of the topology on the objects of category of Frölicher spaces; the extension of the de Rham cohomology theorem in order to establish an isomorphism between the five cohomologies. Beside the algebraic, topological and geometric study of these new objects, the thesis contains a modern formalism of Hamiltonian mechanics on the reduced space under symplectic and Poisson structures.
Mathematical Sciences
D. Phil. (Mathematics)