Presentasjon av masteroppgave: Robert Olav Fauli

Distinguishing between gravity theories with galaxy peculiar velocity statistics

Abstract

The ΛCDM model used in modern cosmology has major theoretical problems. To attempt to solve these many modified gravity theories have been proposed. We calculate velocity statistics (streaming pair-wise velocities and the velocity correlation function) for different models (Hu-Sawicki f(R) and symmetron) using data from n-body simulations. We find that the streaming velocities show the clearest deviations from GR. The F5 model deviates quite strongly, while for symmetron models the time of fifth force turn on is more important than the force range.

We have not accounted for all the sources of variance and covariance, but suggest running many simulations with different realisations of the initial matter distribution to solve this. For future work we suggest calculating the statistics while binning the halos by their environments, and comparing our simulations to observations.

 

Veileder: Professor David F. Mota, Institutt for teoretisk astrofysikk, UiO

Medveileder 1: Postdoktor Philip J. Bull, Institutt for teoretisk astrofysikk, UiO

Medveileder 2: Doktor Claudio Llinares, Institutt for teoretisk astrofysikk, UiO

Intern sensor: Professor Per B. Lilje, Institutt for teoretisk astrofysikk, UiO

Ekstern sensor: Doktor Camille Bonvin, CERN, Sveits

Publisert 28. mai 2015 12:39 - Sist endret 28. des. 2016 11:59