Light-cone cosmology: structure formation in spherical coordinates

• Grant number: 19/04362-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2019
• End date: December 31, 2019
• Field of knowledge: Physical Sciences and Mathematics - Astronomy - Extragalactic Astrophysics
• Principal Investigator: Luis Raul Weber Abramo
• Grantee: Ian Lucas Tashiro
• Host Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Our observations of the Universe represent a very particular cross-section of the large-scale structures: we have access to spherical shells that correspond to earlier epochs as the radii of those shells increase. In other words, what we see are 2D spherical sections of our past light-cone. Furthermore, we cannot really measure the distance, but only the redshift -- which includes both the recession velocity due to the Hubble flow, as well as the peculiar velocities that are generated as a result of the process of structure formation. The goal of this Scientific Initiation project is to study how physical observables, expressed in natural coordinates {z,\theta,\phi}, are related with the theoretical predictions -- which, due to the assumed homogeneity and isotropy of the Universe are naturally described in coordinates ${t,x,y,z}$. In particular, we want to understand how one can extract physical information from the correlation functions and/or power spectra in redshift space, always keeping to the spherical coordinates description.