ABSTRACT:
A six-parameter LCDM model is an excellent fit to the WMAP data, however several types of anomalies (deviations from LCDM) have been reported, especially on large scales (l<20). For example, possible deviations from the isotropy of the universe on large scales have been previously discussed in literature. We do a detailed analysis of the seven and nine year WMAP temperature data for three different flat topologies and obtain bounds for their size using the Feldman-Cousins method. We present a formalism for using the polarization maps to improve these bounds and give forecasts for WMAP and Planck data. We also perform a Markov Chain Monte Carlo (MCMC) Bayesian analysis to constrain two other scenarios of isotropy breaking due to a semiclassical perturbation in the primordial universe.