The effective field theory of large-scale structures and multiple tracers

• Ano de defesa: 2021
• Autor(a) principal: Mergulhão, Thiago Muniz
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Biblioteca Digitais de Teses e Dissertações da USP
• Palavras-chave em Português: Cosmologia; Cosmology; Effective Field Theories; Estrutura em Larga Escala; Large-Scale Structure; Perturbation Theory; Teoria de Perturbação; Teorias Efetivas de Campo.
• Link de acesso: https://www.teses.usp.br/teses/disponiveis/43/43134/tde-14092021-162959/

Modern cosmology has several open problems, many of them stemming from fundamental physics. Two examples of these problems are the lack of information about the nature of dark matter particles, and the mechanism responsible for the accelerated cosmic expansion that we observe. A key source of information that can contribute to solving these issues and many other problems is the distribution of the large-scale structures of the Universe. This motivated us to employ a new model for the description of structure formation, which is based in effective field theories, and to generalize it to treat multiple tracers of the cosmic structures. In order to test our model we performed a series of power-spectrum analysis using results from N-body simulations in real space. Our results show a clear advantage in performing parameter extraction by splitting the tracers into different classes, as compared to the one usually employed in the literature - despite the larger number of free parameters implied by this subdivision. We suppose that our main conclusions will hold in more realistic cases, e.g. in analysis performed in redshift space, as well as with real data.