James Grant is visiting the Mathematical Institute at Oxford today (Monday 28 October) to give a talk in the Partial Differential Equations Seminar series.  The talk is on “Low regularity Riemannian metrics and the positive mass theorem“.  The talk establishes that the positive mass theorem holds for asymptotically flat n-dimensional Riemannian manifolds with a metric that is continuous, lies in the Sobolev space W(loc)(2,n/2), and has non-negative scalar curvature in the distributional sense.  The talk is based on joint work with N. Tassotti and conversations with J.J. Bevan.