High Energy Theory Seminar

Proper time is a simple classical observable, but its correlations are less well understood. We define correlation functions of proper time for massive worldlines coupled to quantum field theory and quantum gravity, and we show how to compute perturbative corrections using Feynman diagrams. 

When the worldline endpoints are held fixed, proper time correlators are derivatives of the on-shell action with respect to mass, or more generally, derivatives of the logarithm of local correlators. These proper time correlators encode correlated path fluctuations. When the worldline endpoints are dynamical and determined relationally in a gravitational system, a proper time delay operator at leading order in the graviton expansion is a smeared graviton operator. The two-point function computes the leading-order signature of quantum gravity in a toy model of a LIGO-type interferometer. This prediction agrees qualitatively with the experimental observable computed in a more realistic model.

The talk is in 469 Lauritsen.

Contact theoryinfo@caltech.edu for Zoom information.