The Problem with Quantum Gravitation

by Herbert W. Hamber (Max-Planck Institute for Gravitational Physics (AEI) and University of California at Irvine)

Tuesday 27 Nov 2012, 16:00 → 18:00 Europe/Rome

Aula Conversi (Dip. di Fisica - Edificio G. Marconi)

Of the four fundamental forces, Gravity is the one that has been studied the longest. Besides being an immediate fact of everyday life, it still presents us today with some of the deepest challenges in contemporary physics.

Einstein’s (classical) relativistic Gravity is unique, in the sense that it influences both the very largest and the very smallest length scales. These include black holes, pulsars, quasars, the Big Bang, and the Universe as a whole, at one end of the spectrum, and the miscroscopic structure of spacetime and unified theories at the other end. Moreover, in spite of being based on some of the most accurately tested principles in science, one of its most basic predictions (gravitational waves) has so far not been detected on earth.

Recent attempts at a quantum theory of Gravity have tried to combine, in a consistent framework, what some have regarded as the two greatest achievements of 20-th century physics, General Relativity and Quantum Mechanics. A major challenge has been to come up with specific predictions that might be tested by observation. The aim of my talk will be to give a very broad brush (and hopefully elementary) survey of our understanding of Gravity and its quantum extension.

Slides Bare.pdf