Observing the oldest light in the Universe from the South Pole: Gravitational waves and more!

by Christian Reichardt (University of Melbourne)

Tuesday May 27, 2025, 11:00 AM → 12:00 PM Europe/Paris

Salle des séminaires (IAP)

The cosmic microwave background (CMB) radiation is the oldest light we can see. Since it bears the imprint of the universe just after the Big Bang (at a mere 0.003% of the universe’s age today), observations of the CMB are a crucial tool in our quest to understand how the Universe began and what its future holds. The South Pole is one of the best sites on Earth for these observations, and is the home of the South Pole Telescope as well as the BICEP Array which together comprise the South Pole Observatory. In this talk, I will discuss two power spectrum measurements from the SPT-3G instrument on the South Pole Telescope. I’ll begin by presenting the latest B-mode measurements from SPT-3G, and consider their implications for inflation. I’ll also preview upcoming measurements of the small-scale temperature power spectrum where the dominant signals are the thermal and kinematic Sunyaev-Zel’dovich (SZ) effects produced by interactions between CMB photons and large scale structure. I will discuss the potential implications the SZ measurements have for the epoch of reionization.