Measuring cosmological parameters with cosmic microwave background experiments

The cosmic microwave background anisotropy is sensitive to the slope and amplitude of primordial energy density and gravitational wave fluctuations, the baryon density, the Hubble constant, the cosmological constant, the ionization history, etc. In this Letter, we examine the degree to which these factors can be separately resolved from combined small- and large-angular-scale anisotropy observations. We isolate directions of degeneracy in this cosmic parameter space, but note that other cosmic observations can break the degeneracy.