Accelerated Lyra's Cosmology Driven by Electromagnetic Field in Inhomogeneous Universe

A new class of cylindrically symmetric inhomogeneous cosmological models for perfect fluid distribution with electromagnetic field is obtained in the context of Lyra's geometry. We have obtained solutions by considering the time dependent displacement field. The source of the magnetic field is due to an electric current produced along the z-axis. Only F12 is a nonvanishing component of electromagnetic field tensor. To get the deterministic solution, it has been assumed that the expansion θ in the model is proportional to the shear σ. It has been found that the solutions are consistent with the recent observations of type Ia supernovae, and the displacement vector β(t) affects entropy. Physical and geometric aspects of the models are also discussed in presence and absence of magnetic field

Lecture Notes on Gauge Theories and Inhomogeneous Cosmologies

These lecture notes were meant to compile the main ideas on gauge field theory and modern cosmology, showing the recent contributions of the author in these areas, including classical thermodynamics, supergravity and quantum gravity. Although the author has conducted the work without wishing to exhaust the issues in question, this synthesis provides some essential formal approaches for further studies, with relevant and updated references, as well as indications of classical readings. Special attention was given to the application of Lyra's geometry, because of its growing importance in quantum cosmology, and to the so-called <<paleogravity>>, a model of supergravity developed by the author with the purpose to offer a classical representation for supergravity that could be made compatible with the quantum theory of spacetime also developed by himself. Also in general cosmology, the emphasis was on inhomogeneous models due to the debate they open on the validity of the standard model. In this sense, the author presented his perturbative formalism of weak gravitational lensing by defining an inhomogeneous cosmological refractive index within a Lemaître-Tolman universe. Lastly, some remarks on Stephani cosmology were organized in order to expose the most significant features of this approach. During the reading, it shall be possible to observe some title marks indicating items of interest, as well as small side texts with outgivings of renowned authors.Key words: gauge field theory, cosmology, Lyra's geometry, quantum gravity, supergravity.====================================================================================================== A presente coletânea de notas de aula foi organizada como compilação das principais idéias sobre teoria de campo de calibre e cosmologia moderna, mostrando as recentes contribuições do autor nessas áreas, incluindo termodinâmica clássica aplicada, supergravidade e gravitação quântica. Embora o trabalho tenha sido conduzido sem pretensões a esgotar os temas em apreço, a síntese produzida trata formalmente alguns aspectos essenciais para estudos posteriores, com referências relevantes e atualizadas, bem como indicações de leituras clássicas. Especial atenção foi dada à aplicação da geometria de Lyra, por sua crescente importância na cosmologia quântica, e à chamada << paleogravidade >>, um modelo de supergravidade desenvolvido pelo autor com o propósito de oferecer uma representação clássica da supergravidade, o qual seria compatível com a teoria quântica do espaço-tempo também desenvolvida pelo autor. Em cosmologia geral, foi dada ênfase em modelos não-homogêneos devido ao amplo debate que eles abrem sobre a validade do modelo padrão. Nesse sentido, o autor apresentou seu formalismo perturbativo de lentes gravitacionais fracas, definindo um índice de refração cosmológico inomogêneo dentro de um universo de Lemaître-Tolman. Por fim, algumas observações sobre a cosmologia de Stephani foram organizadas para expor as características mais significativas dessa abordagem. Durante a leitura, será possível observar algumas marcas indicativas de itens de interesse, bem como pequenos textos marginais com comentários de autores renomados.Palavras-chave: teoria de gauge, cosmologia, geometria de Lyra, gravidade quântica, supergravidade