Measuring Cosmological Parameters with the SDSS QSO Spatial Power Spectrum Analysis to Test the Cosmological Principle

In this paper we emphasize the importance of the Sloan Digital Sky Survey (SDSS) QSO clustering statistics as a unique probe of the Universe. Because the complete SDSS QSO sample covers a quarter of the observable universe, cosmological parameters estimated from the clustering statistics have an implication as a test of the cosmological principle, by comparing with those from local galaxies and other cosmological observations. Using an analytic approach to the power spectrum for the QSO sample, we assess the accuracy with which the cosmological parameters can be determined. Arguments based on the Fisher matrix approach demonstrate that the SDSS QSO sample might have a potential to provide useful constraints on the density parameters as well as the cosmic equation of state.