An Introduction to Shape Dynamics: a New Perspective on Quantum Gravity MCMP – Philosophy of Physics

Sean Gryb (Nijmegen) gives a talk at the Mini-Workshop on the Foundations of Shape Dynamics (23 June, 2014) titled "An Introduction to Shape Dynamics: a New Perspective on Quantum Gravity". Abstract: Shape Dynamics is a theory of gravity where the fundamental ontology is that of evolving conformally invariant spatial geometry. This implements a notion of local spatial scale invariance such that what is seen to be physically meaningful is the information about the local "shapes" (as opposed to size) of a system. Perhaps surprisingly, this theory can be proven to reproduce a vast number of the solutions to the Einstein equations. However, black hole solutions are known to differ from those of GR past the horizon and do not lead to singularities. Shape Dynamics, thus, provides an intriguing new starting point for a theory of quantum gravity. In this introductory chalkboard talk, I will try to give some motivations for Shape Dynamics and will describe the basic structure of the theory, outlining how one can prove equivalence with GR. This will lay the ground work for Tim Koslowski's talk, which will discuss some recent developments of the theory.