Gauge Fields and Quantum Gravity

This colloquium will be given by Daniel Harlow of Princeton University.

Abstract: It has long been expected that the consistency of quantum gravity imposes interesting constraints on electromagnetism. These expectations can be codified as a set of three conjectures of increasing strength: the necessary existence of charged states, the complete population of the charge lattice allowed by the topology of the gauge group, and the weak gravity conjecture.

In this talk I will introduce a new paradox in AdS/CFT, arising when one considers gauge fields propagating in the two-sided AdS-Schwarzschild geometry, whose resolution seems to require all three conjectures to hold. This thus provides a new argument for their validity, and in the case of the weak gravity conjecture it clarifies what the conjecture should have been in the first place. The resolution I propose also has important implications for the emergence of the black hole interior, and more generally for the connection between entanglement and spacetime that has received a lot of attention in recent years.