Title: "Energy Bursts on Cauchy Horizons?"

Certain initial data of the Einstein equations of classical relativity lead to singularities from which world lines emerge. Such singularities are called naked and they lead to loss of predictability beyond a limit called the Cauchy horizon. There is no local characterization of such a horizon in classical relativity. Using quantum fields in curved backgrounds I seek to characterize such horizons. In the example of dust collapse, one finds that the quantum stress tensor diverges on the horizon. I shall discuss this issue and comment on its generality.