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The field equations of the vacuum Quadratic Poincare Gauge Field Theory are expressed in the spin coefficient formalism of Newman and Penrose. These equations are differential identities involving the curvature and torsion, and in this NewmanPenrose type approach must be combined with the generalized Newman-Penrose identities given in chapter 4. The use of this Newman-Penrose type formalism is demonstrated in the derivation of several new classes of exact solutions which would have been impossible to obtain by the various methods being used at this moment in time. This therefore demonstrates the power of the spin coefficient formalism developed in chapter 6. A brief look at SO(3) symmetric space-times, in the context of the vacuum Quadratic Poincare Gauge Field Theory, is taken in chapter 11. As a final consideration, a deeper look at the vacuum Quadratic Poincare Gauge Field Theory itself is taken, in order to see whether or not it is a reasonable Theory of Gravitation.

Thesis (Ph. D.)--University of Washington, 1996. / Vita. Includes bibliographical references (p. [117]-118).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1954. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Issued also under title: Tezisy dokladov pi︠a︡toĭ Mezhdunarodnoĭ konferent︠s︡ii po gravitat︠s︡ii i teorii otnositelʹnosti. / On cover: GR 5. Text in English or French. Includes bibliographical references and index.

Made available in DSpace on 2016-05-17T16:50:51Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-11-10. Added 1 bitstream(s) on 2016-05-17T16:54:28Z : No. of bitstreams: 1 000855056.pdf: 347429 bytes, checksum: 5832dd656116e1e977ebfe0f8f799ea9 (MD5) / Analisamos o espalhamento de partículas quânticas por um campo gravitacional fraco, tratado como campo externo, em primeira e segunda ordens de perturbação. Essa análise acusa violações do Princípio da Equivalência em relação ao spin - em primeira ordem -,e em relação à energia - em segunda ordem. Verificamos que os resultados mencionados são equivalentes àqueles obtidos por intermédio da Teoria Efetiva da Gravitação, no limite em que uma das massas é muito maior do que as outras energias envolvidas. Discutimos também algumas aplicações de nossa investigação, tais como a determinação de um limite superior para a massa do fóton e a possível detecção em um futuro não muito distante dessas violações do Princípio da Equivalência / First and second order corrections for the scattering of different types of particles by a weak gravitational field, treated as an external field, are calculated. These computations indicate a violation of the Equivalence Principle: to first order, the cross-sections are spin dependent; if the calculations are pushed to the next order, they become dependent upon energy as well. Interesting enough, the aforementioned results are equivalent to those obtained by means of the so-called Effective Theory of Gravitation, in the limit in which one of the masses is much greater than all the other energies involved. We discuss also some applications of our research, such as the determination of an upper bound for the photon mass, and the possible detection, in the foreseeable future, of these violations of the Equivalence Principle

The hypothesis adopted in this work is that any permissible metric field whatsoever must satisfy the field equations deduced from an action principle in which the Lagrangian is quadratic in the components of the Riemann curvature tensor. The adoption of such a hypothesis is motivated by the precariousness of the general relativistic interpretation of Mach's principle, which is often used to justify a phenomenological approach to the theory. The quadratic action principle is chosen to provide the fundamental equations of the gravitational field because it is logically and aesthetically appealing, and causes us to lose nothing of the standard relativity theory based on Einstein's vacuum equations. The set of relationships, Rρσ - ½9ρσR = -k Tρσ (Equation) retained as a definition of the matter tensor Tρσ. Attention is concentrated on the solutions of the (generally fourth order) fundamental field equations in the static, spherically symmetric case. Sets of exact, series and numerical solutions are obtained corresponding to certain boundary conditions, or with certain properties in common. Study of the geometrical, topological and physical properties of several of the universes obtained as a result of our hypothesis leads us to believe that our theory is not implausible. We conclude by considering the further possibilities of the theory.

Orientador:José Geraldo Pereira / Banca: Adilson José da Silva / Banca: Alberto Vazquez Saa / Resumo: Neste trabalho, estudaremos as semelhanças e diferenças entre algumas formulações geométricas do Teleparalelismo. Como o fibrado em que estas teorias estão definidas são fibrados com soldagem, novos operadores duais de Hodge podem ser definidos. Usando essa nova definição de dual, construiremos o equivalente teleparalelo da Relatividade Geral de forma autônoma e independente de vínculos externos, e estudaremos alguns pontos de sua dinâmica. Para mostrar a consistência deste novo dual, analisaremos a questão da simetria de dualidade da teoria linearizada / Abstract: In this work, we study some features of different geometrical formulations of teleparallel theories. Since the bundle on which these theories are defined is soldered, a new Hodge dual operator can be defined. Using this new definition of dual, it is possible to construct the teleparallel equivalent of General Relativity, independently of external constraints. Then we study some aspects of its dynamics. To show the consistency of this new dual, we analyze the duality symmetry of the linearized theory / Mestre

Orientador: Antonio Accioly / Banca: José Abdalla Helaÿel-Neto / Banca: Sebastião Alves Dias / Banca: Maria Emilia Xavier Guimarães / BAnca: Ruben Aldrovandi / Resumo: Analisamos o espalhamento de partículas quânticas por um campo gravitacional fraco, tratado como campo externo, em primeira e segunda ordens de perturbação. Essa análise acusa violações do Princípio da Equivalência em relação ao spin - em primeira ordem -,e em relação à energia - em segunda ordem. Verificamos que os resultados mencionados são equivalentes àqueles obtidos por intermédio da Teoria Efetiva da Gravitação, no limite em que uma das massas é muito maior do que as outras energias envolvidas. Discutimos também algumas aplicações de nossa investigação, tais como a determinação de um limite superior para a massa do fóton e a possível detecção em um futuro não muito distante dessas violações do Princípio da Equivalência / Abstract: First and second order corrections for the scattering of different types of particles by a weak gravitational field, treated as an external field, are calculated. These computations indicate a violation of the Equivalence Principle: to first order, the cross-sections are spin dependent; if the calculations are pushed to the next order, they become dependent upon energy as well. Interesting enough, the aforementioned results are equivalent to those obtained by means of the so-called Effective Theory of Gravitation, in the limit in which one of the masses is much greater than all the other energies involved. We discuss also some applications of our research, such as the determination of an upper bound for the photon mass, and the possible detection, in the foreseeable future, of these violations of the Equivalence Principle / Doutor