Gauge-invariant Variables and Entanglement Entropy

Understand

The entanglement entropy (EE) of gauge theories in three spacetime dimensions is analyzed using manifestly gauge-invariant variables defined directly in the continuum.

• Specifically, we focus on the Maxwell, Maxwell-Chern-Simons (MCS), and nonabelian Yang-Mills theories.
• Special attention is paid to the analysis of edge modes and their contribution to EE.
• The contact term is derived without invoking the replica method and its physical origin is traced to the phase space volume measure for the edge modes.