Abstract

Measurements of the CMB have driven our understanding of the universe and the physics that govern its evolution from primordial quantum fluctuations to its present state. They provide the foundation for the remarkable 6-parameter cosmological model, ΛCDM, which fits all cosmological data, although there are some tensions, which may provides hints at new physics. Far from being the last word in cosmology, the model raises deep questions: Is Inflation correct? What is its energy scale? What is the dark matter? What is the nature of dark energy? Are there additional light relic particles? The increasingly sensitive observations of the CMB being made to address these questions also provide powerful and unique probes of astrophysics. This talk will discuss recent experimental developments and observational results, primarily from the 10m South Pole Telescope (SPT), as well as the vision and planning for future CMB measurements, in particular CMB -S4.