The focus of the dissertation "Aspects of cosmic acceleration" is the study of possible mechanisms responsible for the late-time accelerated expansion of the universe. It has 5 main chapters. In... Show moreThe focus of the dissertation "Aspects of cosmic acceleration" is the study of possible mechanisms responsible for the late-time accelerated expansion of the universe. It has 5 main chapters. In the first chapter I have given an overview of modern cosmology. Particularly, an introduction to cosmological perturbation theory, and a general overview of the cosmological standard model, as well as an overview to beyond-standard-model scenarios is presented. Chapter two discusses cosmological models based on the so-called alpha-attractor framework. Chapter three is dedicated to the study of constraints imposed by gravitational wave observations on the so-called doubly-coupled massive bimetric gravity theory. Chapter four studies the cosmological stability of the so-called massive mimetic gravity theory. Finally, Chapter five studies the effect of the Symmetron gravity on the so-called splashback radius of dark matter halos. Show less