16 May 2019 3.00pm
Kellogg Stelle, Imperial College London
Department of Philosophy, Building B Room B7/1140 Campus UAB
The need to quantize gravity was recognized in the 1930s around the time of Dirac’s successful quantization of the electromagnetic field, but not long thereafter Heisenberg found that the dimensional character of Newton’s constant leads to a characteristic problem of divergent integrals for what should be tiny quantum corrections to general relativity. This remains a central problem in quantum gravity, and it has motivated much recent development in the subject. Even though superstring theories finally achieve at least one resolution of the problem, the topic remains a key concern and is cloaked in a certain mystery. The talk will present some personal views on this problem and its relation to current research.
Professor of Physics at Imperial College London. His research focuses on the theory of gravitation, on gauge and supersymmetric field theories and on string theory. He has been a pioneer in the study of higher dimensional extended objects, known as branes, in supersymmetric and string theories, and in the analysis of counterterms for ultraviolet divergences in supersymmetric field theories.
His work has considered in detail the properties of gravitational theories including higher derivative corrections. When corrections quadratic in the curvature tensor are incorporated into the action, he found that this yields a renormalizable quantum system, but at the expense of having negative energy states in the spectrum. Such models also have an enriched set of classical solutions which includes non-Schwarzschild black holes and wormholes.
During his career, he has published around 200 scientific papers and was a 2006 winner of the Alexander Von Humboldt Foundation Research Award.