Primordial Non-gaussianities: theory and prospects for observations

• Grant number: 16/19909-7
• Support Opportunities: Scholarships in Brazil - Master
• Start date: March 01, 2017
• End date: July 31, 2018
• Field of knowledge: Physical Sciences and Mathematics - Physics - Elementary Particle Physics and Fields
• Agreement: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: Luis Raul Weber Abramo
• Grantee: Caroline Macedo Guandalin
• Host Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 12/00800-4 - The 3-D universe: astrophysics with large galaxy surveys, AP.TEM

Abstract

Inflation produces an approximately Gaussian spectrum of scale-independent density perturbations. Deviations from scale independence and from Gaussianity are key indicators of the physical processes behind inflation, and can reveal to us the physical nature of the field(s) responsible for this phase of the Universe. Primordial non-Gaussianity is manifested both in the cosmic microwave background, and in the matter distribution in the Universe. As a result of new planned survey instruments, galaxy maps may be able to constrain $f_{NL}$ (the main parameter that controls non-Gaussianity) better than the Planck satellite has been able to do. It may be possible even to measure parameters which control the ``shape'' of the non-Gaussianities, such as $g_{NL}$. The main difficulties are, of course, the proper control of large-scale systematics, which mix up with the signal we are trying to measure. We have three goals in this project: (1) studying primordial non-Gaussianities and the secondary non-Gaussianities which are generated as a result of non-linear structure formation; (2) determine the level and form of the expected systematics (photometric redshifts, scale-dependent bias, etc.) for some of the recent galaxy surveys, such as J-PAS and PFS; and (3) determining how the multi-tracer technique (Abramo, Secco \& Loureiro, MNRAS 2015) can constrain $f_{NL}$ and $g_{NL}$ in the presence of those systematics. (AU)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

GUANDALIN, Caroline Macedo. Primordial non-Gaussianities: Theory and Prospects for Observations. 2018. Master's Dissertation - Universidade de São Paulo (USP). Instituto de Física (IF/SBI) São Paulo.