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The degeneracy between geometric (Alcock-Paczynski) and dynamic (redshift space) distortions in the pattern of the galaxy distribution has been a long standing problem in the study of the large scale structure of the universe. We examine the possibility of lifting this degeneracy and constraining cosmological parameters by using the Baryon Acoustic Oscillation (BAO) scale as a feature of known physical size, the sound horizon r_s ~ 150 Mpc. We callibrate this scale with the equivalent feature in the Cosmic Microwave Background (CMB). First, we construct a toy model of a power spectrum which includes the BAO as well as geometric and dynamic distortions. By adding a prior onto the sound horizon of ~1% we show, using a Fisher matrix analysis, that error ellipses for line of sight and tangential distortion parameters shrink by a factor of two for a 20(Gpc/h)^3 `DESpec/BigBOSS-like galaxy survey including shot noise. This improvement is even more marked in smaller surveys. We also carry out a Monte Carlo Nested Sampling analysis on our parameter space. We find that Monte Carlo and Fisher methods can agree reasonably well for surveys with large volume but differ greatly for small volume surveys.
Measurements of the cosmic microwave background (CMB) spectral distortions (SDs) will open a new window on the very early universe, providing new information complementary to that gathered from CMB temperature and polarization anisotropies. In this p
We compute the impact of the running of higher order density correlation functions on the two point functions of CMB spectral distortions (SD). We show that having some levels of running enhances all of the SDs by few orders of magnitude which might
The epoch of reionization is one of the major phase transitions in the history of the universe, and is a focus of ongoing and upcoming cosmic microwave background (CMB) experiments with improved sensitivity to small-scale fluctuations. Reionization a
If local supersymmetry is the correct extension of the standard model of particle physics, then following Inflation the early universe would have been populated by gravitinos produced from scatterings in the hot plasma during reheating. Their abundan
We present a general framework for accurate spectral modeling of the low multipoles of the cosmic microwave background (CMB) as observed in a boosted frame. In particular, we demonstrate how spectral measurements of the low multipoles can be used to