R. Bonezzi, HU

Title: “Einstein gravity from worldlines”

In this talk I will present the first-quantized description of Einstein gravity in terms of a point particle model with N=4 local worldline supersymmetries. In particular, I will show that quantum consistency of the underlying first-quantized system produces fully nonlinear Einstein field equations for the target space metric, making this feature not a peculiarity of string theory. As a warmup, I will first present the simpler case of a worldline model with N=2 supersymmetries, describing Yang-Mills, and then move to the recently found results for gravity. In the process, I will try to show that the worldline description allows for the relation between Yang-Mills and gravity to be at least as manifest as the relation between open and closed strings Hilbert spaces. Finally, I will comment on techniques to compute gravitational amplitudes with the model at hand, in particular pure gravity one-loop amplitudes.