## Wormholes, Emergent Gauge fields, and the Weak Gravity Conjecture

**Speaker:**Daniel Harlow, Harvard

**When:**October 14, 2015 (Wed), 03:30PM to 04:30PM (add to my calendar)

**Location:**PRB 595

*This event is part of the HET Seminar Series. *

I will discuss aspects of bulk gauge fields in the AdS/CFT correspondence, arguing that consistency with the microscopic CFT description requires the bulk gauge fields to be "emergent" in a sense that I will make somewhat precise. This leads to a new motivation for (and a clarification of) the "weak gravity conjecture" of Arkani-Hamed, Motl, Nicolis, and Vafa, which is a strengthening of the idea that in a gravitational theory there cannot be gauge fields without charges. My discussion will also give something of a counterexample to the idea of "effective conformal field theory", since we will see that information about high dimension operators in the CFT are sometimes needed to describe low energy experiments in nontrivial backgrounds.