The observation of the Cosmic Microwave Background (CMB) is one of the most powerful probes of our universe. ESA's Planck satellite confirmed that the ΛCDM model works astonishingly well to describe the CMB anisotropies, measuring cosmological parameters with percent-level accuracy. Nevertheless, the Planck results reveal a number of outstanding inconsistencies that might hint at cracks in this very successful model. The most critical one is the Hubble tension, the difference between the expansion rate of the universe measured by the CMB and other early universe probes, versus the rate measured by Type Ia supernovae calibrated with Cepheids.
In this talk I will present the current efforts to shed light on these problems using the South Pole Telescope. SPT is a ground-based CMB experiment which is observing the sky with its latest camera, SPT-3G. It is expected to provide ground-breaking CMB measurements over 25% of the sky. I will show SPT-3G early results, the several innovations we are introducing in the analysis pipeline for our upcoming second data release, and the expectations for the future.
