Speaker: 이승주 박사(IBS 순수물리이론 연구단)
일시: 3월 31일(수) 오후 5시
Title: Quantum Gravity and the Universe
Quantum Field Theory is a modern framework of theoretical physics to describe the quantum dynamics of particles. However, any models of Quantum Field Theory, once coupled to gravity, necessarily break down at very high energies. This talk will address String Theory as a powerful quantum framework for both particles and gravity. While String Theory is originally defined in ten spacetime dimensions, physics in 3+1 dimensions may effectively arise at low energies via compactification, i.e., if the extra spatial dimensions are compact and small. Such effective physics is associated, via precise rules of compactification, to the geometry of a compact space satisfying the string equations of motion. We will first introduce the natural quest for constructing string-theoretical models for the Universe in terms of appropriate compactification geometries, and will discuss challenges as well as the state of the art. Next, switching gears, we will stress that the set of all consistent models of string theory form a perfect arena to study mysterious quantum nature of gravity. Upon motivating recent research activities in the community along this line, we will propose how constraints of quantum gravity are universally realized in string geometry.