Isaac Pliskin (UMass Math&Physics): What is Cartan's Torsion

Students of general relativity or Riemannian geometry are introduced to the Levi-Civita connection: the unique metric-compatible and torsion-free connection on a Riemannian manifold. Classes in these subjects rarely, if ever, address the question of why we want the connection to be torsion-free and the implications of a non-vanishing torsion.  In this talk we will turn to Cartan's original inspirations for generalizing Riemannian geometry, namely Einstein Gravity and Cosserat Elasticity, in an attempt to build a physical intuition for themeaning of torsion within Riemann-Cartan geometry.