In the last few years, we have made remarkable progress in understanding the properties of our observable Universe which appears to have evolved from a hot Big Bang 13.7 billion years ago. The fine-tuning of initial conditions required to reproduce our present day Universe suggests that our Universe may merely be a region within an eternally inflating super-region. Many other regions could exist beyond our observable Universe with each such region governed by a different set of physical parameters than the ones we have measured for our Universe. Collision between these regions, if they occur, should leave signatures of anisotropy in the cosmic microwave background. I present spatial and spectral analysis of the cosmic microwave background data from Planck. I will focus on constraining properties at the epoch of recombination 270,000 years after the Big Bang and present the observational evidence in favor of alternate Universes.
Talk Host: Jacqueline Hewitt