My research interests are in stellar dynamics, a field at the interface between astronomy, physics, and applied mathematics. I specialise in the dynamics of collisional stellar systems, such as star clusters and galactic nuclei, which I study by means of analytical, numerical, and observational approaches.
My investigation of the role of internal rotation, velocity anisotropy, and external tidal perturbations has unveiled an unexpected degree of ‘phase space richness’ in star clusters and has brought a new, more realistic, perspective on their classical dynamical paradigm.
From an astrophysical viewpoint, I am interested in the formation and evolution the low-mass stellar systems which define the intriguing boundary between our current notions of ‘star clusters’ and ‘dwarf galaxies’. This is a central challenge for ‘near-field’ cosmology in the era of Gaia, LIGO and JWST — with wide-ranging implications for fundamental physics. My activities are crystallised around three open questions: How did the first stellar aggregates form in the early universe? Is there a ‘missing link’ between stellar and super-massive black holes? Where is the limit for the presence of the invisible ‘dark’ matter on small astrophysical scales?
From an applied mathematics viewpoint, I am interested in a number of topics broadly connected to the classical gravitational N-body problem, especially Vlasov-Poisson equilibria and related perturbation and asymptotic methods for elliptic PDEs, kinematic complexity in statistical mechanics of self-gravitating systems, kinetic counterparts of the theory of rotating fluids, and integrability and numerical methods for Hamiltonian systems. I also have a growing interest in developing techniques from Bayesian statistics and machine learning for application to astrophysical data and to a wider range of problems in small and big data science.