Christian Wüthrich: Quantum gravity: motivations and implications — 6/20/16

Описание: Abstract: "Do we need to quantize gravity, as it is tacitly assumed in much of fundamental physics? Even though the standard lore falls short of justifying an affirmative answer, the fact that matter is not classical requires our going beyond general relativity. Though conclusive in this respect, this fact offers no guidance as to the direction in which a quantum theory of gravity must be sought. Despite its being unobserved to date, Hawking radiation and black hole thermodynamics is widely considered our firmest hint, weak though it may be. As the theoretical derivation of Hawking radiation and black hole thermodynamics relies on a semi-classical mélange of physical principles, it raises the question of whether we need the unified blend of a full quantum theory of gravity at all, particularly given that the latter is generally expected to reject at least some of the principles of the former. Although this issue is not settled, it seems as if the difficulties in articulating a semi-classical theory can only be overcome in full quantum gravity.

This will lead us to the second part of my talk, in which I will sketch some of the philosophical and foundational problems that come up in quantum gravity and that will be addressed in various lectures and discussions throughout the week. The vantage and focal point for many of these issues will be the apparent disappearance of spacetime in full quantum theories of gravity."

Title Image by Kaca Bradonjic (http://kacabradonjic.com)