New insights into galaxy formation and evolution

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Buried within our galactic backyard is a treasure trove of information about how our galaxy, the Milky Way, formed and evolved. The field of "galactic archaeology" sets out to uncover and decipher the implications of this information both for our galaxy and galaxy formation in general. In the next decade, galactic archaeology is about to undergo a revolution as the European Space Agency's Gaia mission will provide exquisite new observations of the stellar positions of over a billion stars and true motions of tens of millions. Combined with upcoming surveys of the chemical signatures of stars (stars with similar chemical signatures were likely formed together) we will then be able to piece together their evolution back in time. The first part of my research program outlines a series of simulations on parallel computers that will introduce new levels of fidelity into our studies of galactic archaeology, and enable us to model upcoming data from the Gaia survey (and others) with great precision. Step-by-step I will increase physical complexity so as to eventually include all the dominant physical processes present in the Milky Way.The second part of the research program will focus on how black holes, once thought to be largely irrelevant in the process of galaxy formation, can actually directly determine the evolution of the largest galaxies. Due to the presence of an accretion disk around them, black holes actually liberate and return vast amounts of energy to their surrounding galaxy. But describing this process is immensely difficult. Even supermassive black holes, with masses tens of millions of times that of the Sun, are tiny compared to the overall size of a galaxy - the ratio is akin to a grain of sand and the entire Earth. The research outlined in this proposal will improve our modelling of this process by adding greater physical complexity and also allowing us to follow the energy that flows out from black holes to large radii where it interacts with the rest of the galaxy.