https://repositorio.ufpb.br/jspui/handle/123456789/4 Mon, 06 Apr 2026 12:07:06 GMT 2026-04-06T12:07:06Z https://repositorio.ufpb.br/jspui/handle/123456789/37882 Título: Gravidade quântica a baixas energias: correções fenomenológicas da mecânica quântica Autor(es): Sampaio, Kelvin Costa Rocha Orientador: Lobo, Iarley Pereira Abstract: This study aims to explore how quantum systems and decoherence characteristics impact the field of quantum gravity, highlighting the importance of phenomenological models that bridge microscopic-scale effects with observable observations. The research includes a review of the theoretical principles of quantum mechanics and relativity, emphasizing suggestions for systematic and stochastic modifications in kinematics inspired by quantum gravity scenarios. Furthermore, the observational consequences and limitations of the models in question are highlighted, connecting the formulated theory to possible effects that can be detected at accessible energies. The findings suggest that, although quantum gravity remains an open challenge, phenomenological analyses may offer interesting clues for future investigations and experiments. Editor: Universidade Federal da Paraíba Tipo: TCC Fri, 03 Oct 2025 00:00:00 GMT https://repositorio.ufpb.br/jspui/handle/123456789/37882 2025-10-03T00:00:00Z https://repositorio.ufpb.br/jspui/handle/123456789/34796 Título: Um estudo da eletrodinâmica acoplada a férmions e alguns aspectos da mecânica quântica relativística Autor(es): Guinote, Bárbara Vitória Silva Orientador: Porfírio, Paulo José Ferreira da Silva Abstract: This work seeks to explore the foundations of Classical and Quantum Field Theory, establishing a bridge between Classical Mechanics and modern concepts such as symmetry and gauge invariance. It begins by developing the variational and tensorial formalism required to understand the transition from classical physics to field formulations. Then, electromagnetism is examined from the perspective of a gauge theory, with emphasis on the covariance of Maxwell’s equations and the distinction between global and local symmetries. The study also addresses the gauge principle and its role in quantum mechanics. Finally, relativistic quantum mechanics is introduced through the Klein-Gordon and Dirac equations, discussing their solutions, probability currents, and the famous Dirac Sea interpretation. This study aims to provide a solid conceptual and mathematical foundation for understanding the fundamental theories governing physical interactions in various regimes. Editor: Universidade Federal da Paraíba Tipo: TCC Mon, 05 May 2025 00:00:00 GMT https://repositorio.ufpb.br/jspui/handle/123456789/34796 2025-05-05T00:00:00Z https://repositorio.ufpb.br/jspui/handle/123456789/34469 Título: Um estudo das soluções de buracos negros na relatividade geral Autor(es): Nascimento, Tarcila Ferreira Domingues do Orientador: Silva, Paulo José Ferreira Porfírio da Abstract: In this work, we investigate some of the exact solutions for black holes in the context of general relativity, focusing on the Schwarzschild and Reissner-Nordström metrics. Based on the foundations of special relativity, differential geometry, and general relativity, the necessary mathematical framework was developed to analyze these solutions. For the Schwarzschild case, the spacetime structure, the singularity at r = 0, and the event horizon at r = 2GM were examined. The Reissner-Nordström solution was analyzed, revealing the existence of two horizons (r±) and discussing the physical implications of the electric charge Q. The results demonstrate how these theoretical solutions are now supported by observational evidence through modern techniques, such as the first image of a black hole captured by the Event Horizon Telescope. Editor: Universidade Federal da Paraíba Tipo: TCC Fri, 25 Apr 2025 00:00:00 GMT https://repositorio.ufpb.br/jspui/handle/123456789/34469 2025-04-25T00:00:00Z https://repositorio.ufpb.br/jspui/handle/123456789/33239 Título: Método de aplicação de Redes Neurais Convolucionárias (CNN) para identificação de fusões de galáxias em dados simulados pelo Projeto Illustris Autor(es): Almeida, Natali Cristina Moreira de Orientador: Cavalcante, Hugo Leonardo Davi de Souza Abstract: Since its origin, the universe has been in constant evolution, which includes the formation and destruction of black holes, galaxies, stars, and other cosmological structures. Observing this evolution allows us to understand, discover, and test models and theories related to the foundations of physics, such as the Big Bang, relativity, the existence of dark matter and dark energy, etc. In addition to experimental observation, theoretical models can be tested in computer simulations, in which theoretical variables can be directly controlled and time accelerated or reversed, allowing analyses that are impossible to perform on real scales. Recent models, however, produce a vast amount of data, which makes their manual analysis difficult. The same is true for the vast amount of images acquired by the Hubble Space Telescope (HST) and James Webb Space Telescope (JWST). To facilitate this analysis, we demonstrate here the use of convolutional neural networks (CNNs) to identify galaxy mergers in data simulated by the Illustris project. We successfully reproduced some results from the literature, improving the hyperparameters of the neural network to allow faster and more reliable convergence. Data collection was performed on open-access platforms, GitHub, and the Space Telescope Science Institute (STSI). The source code developed is also made available to the community so that it can be used in this and other problems and improved. We hope to contribute to the use of neural networks and artificial intelligence not only in astrophysics but also in other problems that require image classification and that have a large database. Editor: Universidade Federal da Paraíba Tipo: TCC Fri, 25 Oct 2024 00:00:00 GMT https://repositorio.ufpb.br/jspui/handle/123456789/33239 2024-10-25T00:00:00Z