Theory HEP Seminar

Searching for early-universe relics in the CMB

Matthew Johnson

Perimeter Institute

A number of theoretically well-motivated extensions of the standard cosmological model predict weak signatures in the form of spatially localised sources embedded in the cosmic microwave background. I will discuss two such extensions: theories giving rise to cosmic textures (a type of topological defect) and theories giving rise to cosmic bubble collisions in the context of eternal inflation. I will then present a hierarchical Bayesian statistical formalism and a complete data analysis pipeline for testing such scenarios, and discuss results from an analysis using WMAP 7-year data.