Dr Andreas Stergiou
Royal Society University Research Fellow
Andreas studied physics at the National and Kapodistrian University of Athens, graduated with a master’s degree in theoretical physics from the University of Amsterdam, and obtained his PhD at the University of California, San Diego. Subsequently, he held postdoctoral positions at Yale University, CERN, and Los Alamos National Laboratory. In 2021, he was awarded a University Research Fellowship from the Royal Society and joined King’s College London.
Andy’s research spans a variety of topics in quantum field theory (QFT). He is an expert on the renormalisation group (RG), conformal and superconformal field theories and their applications.
High-energy experiments are performed at different energy scales and it has been observed that parameters such as interaction strengths depend on the energy scale. This dependence is described by the RG, and the associated QFTs are said to evolve along RG flows. A common feature of RG flows is that at energies sufficiently high or low the energy-scale dependence diminishes until it completely disappears. Fixed points of RG flows are then reached, and it turns out that the QFTs that live at these fixed points have special, emergent properties: they are scale invariant and in fact conformal. Conformal field theories (CFTs) have additional symmetries compared to QFTs along RG flows, something that enables the development of new tools and methods for their study.
Andy's research aims to chart the space of CFTs and the RG flows that connect them. He is motivated by applications of these ideas to critical phenomena, condensed matter physics, particle physics, gravity and string theory. He spends most of his time researching formal and applied aspects of RG flows and conformality in these areas, and is interested both in developing new methods for these studies as well as applying these methods to areas where they have not been previously used in order to solve outstanding problems.