Cosmology in the era of quantum gravity

My project will explore the realization of cosmic horizons within quantum gravity. Understanding the existence of long-lived cosmic acceleration in ultraviolet-complete effective field theories is an open problem. Cosmological observations urge high-energy physics to settle this debate theoretically, as well as on the model-building side.In the search for string-theoretic solutions exhibiting long-lived cosmic acceleration, my study will focus on two aspects: the theoretical implications of cosmic horizons, and the distinctive phenomenological features of effective theories selected by consistent models of quantum gravity. Through advanced methods from dynamical systems and knowledge of asymptotic corners of the string landscape, my work will include theories with large field excursions for scalars with kinetic couplings to pseudo-scalars, as well as models with direct couplings between dark energy and dark matter, cosmological stasis, early kination, and the axiverse.