bstract: I propose an energy-spacetime uncertainty principle. The average null energy in a small region of spacetime can be very negative, while the average over a larger region cannot be as negative. I will prove this result within free field theory, and discuss the prospects for more general proofs, as well as the implications for singularity theorems. Reference: https://arxiv.org/abs/2111.05772
 
 https://berkeley.zoom.us/j/370438207 (virtual-zoom)