Unlocking the nonlinear Universe: An odyssey into black-hole feedback

It is an exciting time for cosmology. The next generation of weak-lensing surveys will map the matter distribution of the Universe with extraordinary precision, opening a new window on dark matter, dark energy, and fundamental physics. But much of this promise lies on nonlinear scales, where predictions are limited by our understanding of astrophysical processes.

I will describe our unexpected odyssey into black-hole feedback. By combining weak lensing with galaxy surveys, X-ray observations, and CMB measurements of the thermal and kinematic Sunyaev–Zel’dovich effects we can map the matter, electrons, and pressure around galaxies—and reveal how energetic processes, such as supermassive black-hole feedback, redistribute them. Remarkably, these independent observations seem to point in the same direction: black-hole feedback may be too powerful, ejecting more gas than expected; too efficient, pushing it to remarkably large distances; and somehow too cool, producing less thermal pressure than predicted.I will discuss what might explain this emerging picture, how it is already sharpening weak-lensing cosmology, and how new probes such as fast radio bursts could help turn this astrophysical challenge into a route to unlocking the nonlinear Universe.

Biography: Professor Amon and her group are focussed on the ground-breaking Rubin Observatory’s Legacy Survey of Space and Time, which will image more than 1 billion galaxies. They use galaxies to map the large-scale structure and confront questions about the composition and evolution of our Universe. Ultimately, their goal is to understand the nature of dark matter and dark energy. (Taken from personal website)