title: Evolution and observational signatures of cosmic structures
creator: Jürgens, Gero
subject: ddc-530
subject: 530 Physics
description: Two main topics form the content of this thesis. In the first part, non-linear cosmological structure formation is studied within the time renormalization group (TRG) formalism. The tree-level perturbative trispectrum was included in the time evolution of the bispectrum. Using Gaussian initial growing mode conditions we achieved an improvement in the predictions of the dark matter power spectrum in the mildly non-linear regime. We reached percent accuracy for wave numbers k < 0:18 h/Mpc for redshift z = 1, while for k > 0:25 h/Mpc the perturbative description of the trispectrum breaks down. Our results emphasize the importance of higher order correlators for the  non-linear power spectrum evolution, but the fast increase in numerical cost limits the applicability of the TRG method.  Subject of the second part are signal-to-noise estimates for possible cross-correlation measurements between the integrated Sachs-Wolfe (iSW) effect and the tracer galaxy density field assuming data from the Planck mission and a Euclid-like galaxy survey. Orthogonalized polynomial line-of-sight weighting functions for the galaxy field are employed to resolve tomographical information of the cross-spectrum. For the equation-of-state parameter w = -0.9 our tomographic method provides a 15% increase in the signal-to-noise ratio Sigma of the cross-spectrum (10% for w = -1.0). Furthermore, cross-bispectra and cross-trispectra are studied with respect to a possible detection of the non-linear iSW effect. Finding values of Sigma = 0.83 for the mixed bispectrum <tau gamma^2> and Sigma = 0.19 in case of the trispectrum <tau gamma^3>, the effect has to be regarded as undetectable in correlations with future galaxy surveys.
date: 2013
type: Dissertation
type: info:eu-repo/semantics/doctoralThesis
type: NonPeerReviewed
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserverhttps://archiv.ub.uni-heidelberg.de/volltextserver/14633/1/phd_juergens_online.pdf
identifier: DOI:10.11588/heidok.00014633
identifier: urn:nbn:de:bsz:16-heidok-146335
identifier:   Jürgens, Gero  (2013) Evolution and observational signatures of cosmic structures.  [Dissertation]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/14633/
rights: info:eu-repo/semantics/openAccess
rights: http://archiv.ub.uni-heidelberg.de/volltextserver/help/license_urhg.html
language: eng