Cosmic Complementarity: Joint Parameter Estimation from Cosmic Microwave Background Experiments and Redshift Surveys

Abstract

We study the ability of future cosmic microwave background anisotropy experiments and redshift surveys to constrain a 13-dimensional parameterization of the adiabatic cold dark matter model. Each alone is unable to determine all parameters to high accuracy. However, considered together, one data set resolves the difficulties of the other, allowing certain degenerate parameters to be determined with far greater precision. We treat in detail the degeneracies involving the classical cosmological parameters, massive neutrinos, tensor-scalar ratio, bias, and reionization optical depth as well as how redshift surveys can resolve them. We discuss the opportunities for internal and external consistency checks on these measurements. Previous papers on parameter estimation have generally treated smaller parameter spaces; in direct comparisons to these works, we tend to —nd weaker constraints and suggest numerical explanations for the discrepancies. Subject headings: cosmic microwave backgroundcosmology: theorydark matter ¨ large-scale structure of universemethods: numerical