Coherent state superpositions, entanglement, and gauge/gravity correspondence

Abstract

We focus on two types of coherent states, the coherent states of multi-graviton states and the coherent states of giant graviton states, in the context of gauge/gravity correspondence. We conveniently use a phase shift operator and its actions on the superpositions of these coherent states. We find N-state Schrödinger cat states, which approach the one-row Young tableau states, with fidelity between them asymptotically reaching 1 at large N. The quantum Fisher information of these states is proportional to the variance of the excitation energy of the underlying states and characterizes the localizability of the states in the angular direction in the phase space. We analyze the correlation and entanglement between gravitational degrees of freedom using different regions of the phase space plane in bubbling AdS. The correlation between two entangled rings in the phase space plane is related to the area of the annulus between the two rings. We also analyze two types of noisy coherent states, which can be viewed as interpolated states that interpolate between a pure coherent state in the noiseless limit and a maximally mixed state in the large noise limit.