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Cosmological parameters in precision cosmology

Record Type:	Electronic resources : Monograph/item
Title/Author:	Cosmological parameters in precision cosmology
Author:	Wang, Xiaomin.
Description:	204 p.
Notes:	Source: Dissertation Abstracts International, Volume: 65-03, Section: B, page: 1367.
Notes:	Supervisor: Max Tegmark.
Contained By:	Dissertation Abstracts International65-03B.
Subject:	Physics, Astronomy and Astrophysics.
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3125914
ISBN:	049673203X

Cosmological parameters in precision cosmology
Wang, Xiaomin.

Cosmological parameters in precision cosmology [electronic resource] - 204 p.

Source: Dissertation Abstracts International, Volume: 65-03, Section: B, page: 1367.

Thesis (Ph.D.)--University of Pennsylvania, 2004.

Finally, we present a useful fast method to compute cosmological parameters by combining WMAP and other data, based on fitting the WMAP likelihood surface to the exponential of a quartic or sextic polynomial. This method is accurate up to Delta ln L &sim; 0.05 over the 2sigma region of the parameter space.

ISBN: 049673203XSubjects--Topical Terms:

227131
Physics, Astronomy and Astrophysics.

Cosmological parameters in precision cosmology
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300 $a 204 p.
500 $a Source: Dissertation Abstracts International, Volume: 65-03, Section: B, page: 1367.
500 $a Supervisor: Max Tegmark.
502 $a Thesis (Ph.D.)--University of Pennsylvania, 2004.
520 # $a Finally, we present a useful fast method to compute cosmological parameters by combining WMAP and other data, based on fitting the WMAP likelihood surface to the exponential of a quartic or sextic polynomial. This method is accurate up to Delta ln L &sim; 0.05 over the 2sigma region of the parameter space.
520 # $a First, we perform a detailed analysis of CMB, galaxy and Lyman-alpha forest clustering, both alone and jointly. We test for and find consistency both within each category of experiments and between them. We then compute constraints on 11 parameters of an adiabatic inflationary cosmological model using different data sets. Our best fit model is robust and agrees with all data available up to year 2001, in good agreement with results from other teams. We also obtain some sharp constraints that were new at the time, e.g., a neutrino mass range 0.04--4.2eV .
520 # $a In this dissertation, we use a variety of methods and tools to constrain cosmological models and their free parameters.
520 # $a Second, we explore the possibility of weak gravitational lensing as another tool to study cosmological parameters. We treat the measured aperture mass variance curve analogously to the CMB and galaxy power spectra. Using lensing results from the RCS experiment, CMB results up to Archeops 2002, and galaxy clustering data from 2dFGRS, both separately and jointly, we do a 9-parameter analysis. We find that CMB and 2dF data are consistent with a flat adiabatic scale-invariant model with OΛ = 0.72 +/- 0.09, h2Ocdm = 0.115 +/- 0.013, and h2Ob = 0.024 +/- 0.003 (all 68%CL), and that lensing helps further tighten the constraints. However our results also reveal that there is tension regarding some parameters such as power spectrum normalization sigma8, and we discuss possible solutions to this problem. Comparing our results with the subsequent WMAP results from 2003 shows remarkably good agreement both on the CMB power spectrum and on cosmological parameters, which means that precision cosmology has passed an important test.
520 # $a Third, we compute constraints on cosmological parameters using the 3D galaxy power spectrum from SDSS combined with WMAP and other data up to October 2003. We find our flat adiabatic ACDM model constraints in agreement with both our pre-WMAP results and the WMAP team WMAP+2dF analysis, which means a consistency check has been passed also for independent galaxy redshift surveys. We emphasize particularly the physical origin of the constraints.
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773 0 # $g 65-03B. $t Dissertation Abstracts International
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790 1 0 $a Tegmark, Max, $e advisor
791 $a Ph.D.
792 $a 2004
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