Sobre a possibilidade de efeitos quântico-gravitacionais modificarem o destino do universo

• Ano de defesa: 2007
• Autor(a) principal: Barboza Junior, Edésio Miguel
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Programa de Pós-graduação em Física; Física
• Palavras-chave em Português: Cosmologia quântica; CNPQ::CIENCIAS EXATAS E DA TERRA::FISICA
• Link de acesso: https://app.uff.br/riuff/handle/1/19116

In this work we perform the quantization of a flat Friedmann-Robertson-Walker cosmological model dominated by the so-called phantom energy. The classical model presents an accelerated expansion ending in a Big Rip, a future singularity characterized by the divergence of the scale factor and the energy density a finite time from now. When this singularity is approached, the energy scale becomes comparable to the Planck scale and the gravitational field intensity becomes comparable to the intensity of the other basic interactions, suggesting that close to the Big Rip quantum-gravitational effects become increasingly important. Since in many cases the quantization is strong enough to prevent past singularities like the Big Bang, is natural to ask if quantum effects can prevent the future singularity. To answer this question, we perform the quantization in three different ways, which in turn supply universes that evolve in the same way. We observe that the same catastrophic end of the universe that appears in the classical model is predicted by the quantum model.