Talk page
Title:
Entanglement entropy and space-time geometry of the rainbow chain
Speaker:
Abstract:
The rainbow chain is an inhomogenous free fermion model where the hopping amplitudes decrease exponentially from the center of the chain towards the two end points. In the strong inhomogeneity limit the ground state is made of singlets that connect the left and right halves of the chain. Hence, the entanglement entropy of the half-chain is linear in the size of the chain. This property remains true for weak inhomogeneities, where one can apply field theory methods to show that the ground state is a thermofield double characterized by a temperature relate to the inhomogeneity parameter denoted by h. One also finds that the rainbow model is described by a Dirac fermion moving in a spacetime with constant negative curvature equal to -h^2. The rainbow chain provides a simple model where to analyze in great detail the relation between entanglement and spacetime.
Link:
Workshop: