Seminar:- Quadratic Gravity: From Weak to Strong
More than three decades ago, quadratic gravity was found to present a perturbative, renormalizable and asymptotically free theory of quantum gravity. Unfortunately the theory appeared to have problems with a spin-2 ghost. In this talk, the speaker will revisit quadratic gravity in a different light by considering the case that the asymptotically free interaction flows to a strongly interacting regime. This occurs when the coefficient of the Einstein-Hilbert term is smaller than the scale that the quadratic couplings grow strong. Here QCD provides some useful insights. By pushing the analogy with QCD, she conjectures that the non-perturbative effects can remove the naive spin-2 ghost and lead to the emergence of general relativity in the IR, with the Planck mass identified as the strong gravity scale. This theory has new static spherically symmetric.
地點：香港科技大學 李兆基校園 盧家驄薈萃樓 賽馬會高等研究院 4042室
講者：Dr Jing Ren (University of Toronto)