Black holes and their host galaxies: coevolution across cosmic time

Galaxy formation is one of the most fascinating yet challenging fields of astrophysics. The desire to understandgalaxy formation has led to the design of ever more sophisticated telescopes which show a bewildering varietyof galaxies in the Universe. However, the degree to which an interpretation of this wealth of data can succeeddepends critically on having accurate and realistic theoretical models of galaxy formation. While cosmologicalsimulations of galaxy formation provide the most powerful technique for calculating the non-linear evolution ofcosmic structures, the enormous dynamic range and poorly understood baryonic physics are main uncertaintiesof present simulations. This impacts on their predictive power and is the major obstacle to our understanding ofobservational data. The objective of this proposal is to drastically improve upon the current state-of-the-art by i)including more realistic physical processes, such as those occurring at the sphere of influence of a galaxy’s centralblack hole and ii) greatly extending spatial dynamical range with the aid of a novel technique I have developed.With this technique I want to address one of the major unsolved issues of galaxy formation: “How do galaxies andtheir central black holes coevolve?” Specifically, I want to focus on three crucial areas of galaxy formation: a) Howand where the very first black holes form, what are their observational signatures, and when is the coevolution withhost galaxies established? b) Is black hole heating solely responsible for the morphological transformation andquenching of massive galaxies, or are other processes important as well? c) What is the impact of supermassiveblack holes on galaxy clusters and can we calibrate baryonic physics in clusters to use them as high precisioncosmological probes? The requested funding is for 50% of the PI’s time and three postdoctoral researchers toestablish an independent research group at the KICC and IoA, Cambridge.