Revealing the Structure of the Universe: From Extreme Gravity to Exoplanets

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This is an ambitious proposal to advance our understanding of the structures observed in our Universe, ensuring the development of world-leading research in areas central to the Science Challenges in the STFC roadmap:Confronting inflationary scenarios: The standard inflationary paradigm, in which the observed galaxies and other large-scale structure originated from quantum fluctuations in the early universe, is now being probed with increasing precision using Planck satellite and galaxy survey data. We will develop robust predictions from inflationary models and test these with a detailed statistical analysis of huge galaxy surveys and cosmic microwave maps. We will also advance our understanding of gravitational collapse to more precisely predict the distribution of galaxies in our Universe.Scalar fields in the universe: from theory to observation: We will explore how astronomical observations can provide new information about fundamental physics. In particular, we will investigate whether there is astronomical evidence for additional scalar fields in the Universe which might lead to significant modifications to Einstein's theory of general relativity or other signatures. We will perform N-body simulations of clusters of galaxies to make precise observational predictions. Black Holes and Gravitational Physics: Gravitational waves are ripples in spacetime which form when black holes or neutron stars merge or in the supernova explosion of stars. They propagate across the universe at the speed of light and will enable us to view the universe in a qualitatively new way with gravitational wave detectors, like Advanced LIGO which are currently listening for these signals. We will study numerically and analytically the stability of black holes and the shape of their gravitational wave signals to help in this search. Dynamics of Accretion Discs: Gaseous discs around young stars and black holes are ubiquitous in the Universe and drive some of its most fascinating and important processes. Of these this project addresses: warping of discs around black holes and in binary star systems, the great outbursts of energy that characterise nascent stellar systems and dwarf novae, and high-frequency oscillations from luminous discs around black holes. The thread linking these diverse phenomena is turbulence and magnetic fields in the gas, which we study through large-scale numerical simulations.Formation, Evolution and Dynamics of Exoplanets: Planets are formed in dusty gaseous discs around young stars. We will study the properties of giant vortices in which solid material may be accumulated, examine the growth of newly formed planets as they accrete gas from the surrounding disc, discover how planets are heated by waves in the surrounding disc, and quantify the interactions between planets and their neighbours.Tidal Interactions of Planets, Stars and Discs: We will study the long-term evolution of extrasolar planetary systems through their tidal interactions with the central star, which affect the spin and orbital motion and can cause planets to swell, migrate inwards and even be destroyed. We will also study the gravitational interactions of planets with the protoplanetary disc, which can generate large waves, cause elliptical motion or completely truncate the disc.