Speaker
Description
In this talk, I'll start with the Cosmological Principle and its ramifications for the Cosmic Microwave Background Radiation. Mathematically speaking, statistical isotropy implies nonzero correlations between spherical harmonic coefficients $\left
To explain this effect a large number of models have already been given. But in our work, we were interested in the possibility of explaining it using the modified primordial power spectrum. It is argued that by introducing `some' anisotropy and/or inhomogeneity, we can explain this effect. After mathematical analysis, $l^{\prime}=l+1, m^{\prime}=m$ are concomitantly found with the usual isotropic ones. By defining a statistic and subsequent $\chi^2$ analysis, model parameters are extracted.
I'll also show that the ab initio derivation of the anisotropic primordial power spectrum can't be done in the commutative spacetimes. It is found that the same kind of form (apart from some extra correlations) can be derived in noncommutative spacetimes.
Summary
Hemispherical power asymmetry in an anomaly in CMB that violates the Cosmological Principle of standard Cosmology and was found in 2004 in the WMAP data. Although a large number of models have been given to explain this effect, I would instead like to discuss the same effect on the basis of modified primordial power spectrum based models. In the standard paradigm, the primordial power spectrum is homogeneous and isotropic. But it will be shown that by allowing inhomogeneity and/or anisotropy, one can account for this anomaly. In particular, I'll show how the anisotropic power spectrum can be derived using the noncommutative spacetimes.
