eprintid: 17645
rev_number: 12
eprint_status: archive
userid: 1448
dir: disk0/00/01/76/45
datestamp: 2014-11-06 10:41:05
lastmod: 2014-11-10 11:00:19
status_changed: 2014-11-06 10:41:05
type: doctoralThesis
metadata_visibility: show
creators_name: Beyer, Joschka Johannes
title: Aspects of cosmic structure formation in coupled scalar field dark matter models
subjects: ddc-500
subjects: ddc-530
divisions: i-130300
adv_faculty: af-13
abstract: In this thesis we introduce a novel coupled two scalar field model of the dark sector motivated by
higher dimensional dilatation symmetric theories of gravity, which could potentially provide a solution
to the cosmological constant problem. This work is split up into four parts. First, we motivate
the model and discuss its evolution at the background level. We find a quintessence-type scaling
solution in the early universe and a coupled cold dark matter scenario for later times. At the level of
linear perturbations we introduce an effective fluid description of this model and implement it into
a Boltzmann-code to recover the linear power spectrum, which exhibits a characteristic suppression
of power at a Jeans scale. In a third step we analyze superhorizon perturbations in the early universe
in some detail, with particular focus on the issue of the stability of the adiabatic perturbation mode.
Finally we apply the extended Press-Schechter formalism to predict substructure abundances within
a typical galaxy like the Milky Way and use the results to obtain parameter bounds for our model.
date: 2014
id_scheme: DOI
id_number: 10.11588/heidok.00017645
ppn_swb: 1659476674
own_urn: urn:nbn:de:bsz:16-heidok-176458
date_accepted: 2014-10-29
advisor: HASH(0x55fc36c28000)
language: eng
bibsort: BEYERJOSCHASPECTSOFC2014
full_text_status: public
citation:   Beyer, Joschka Johannes  (2014) Aspects of cosmic structure formation in coupled scalar field dark matter models.  [Dissertation]     
document_url: https://archiv.ub.uni-heidelberg.de/volltextserver/17645/1/dissertation_beyer_2014.pdf