Entanglement Entropy in Flat Holography

The appearance of BMS symmetry as the asymptotic symmetry of Minkowski spacetime suggests a holographic relation between Einstein gravity and quantum field theory with BMS invariance, dubbed BMSFT. With a three dimensional bulk, the dual BMSFT is a non-Lorentz invariant, two dimensional field theory with infinite-dimensional symmetries. In this talk, I will argue that entanglement entropy in BMSFT can be described by a swing surface in the bulk. For a single interval at null infinity, the corresponding swing surface consists of two ropes which are null geodesics emanating from the entangling surface at the boundary, and a bench, which is a spacelike geodesic extremizing the distance between the ropes.