Witten effect, anomaly inflow, and charge teleportation

Understand

We study a phenomenon that electric charges are "teleported" between two spatially separated objects without exchanging charged particles at all.

• For example, this phenomenon happens between a magnetic monopole and an axion string in four dimensions, two vortices in three dimensions, and two M5-branes in M-theory in which M2-charges are teleported.
• This is realized by anomaly inflow into these objects in the presence of cubic Chern-Simons terms.
• In particular, the Witten effect on magnetic monopoles can be understood as a general consequence of anomaly inflow, which implies that some anomalous quantum mechanics must live on them.