Wormholes in Quantum Mechanics
Herman Verlinde
TL;DR
The work extends wormhole physics beyond gravity by defining a geometric path integral for wormhole partition functions in a broad class of quantum systems derived from phase-space quantization. It shows that the $n$-fold wormhole partition function is the $n$-th Rényi entropy of a thermo-mixed double state, realized via a replica construction that isolates contributions from different quantum numbers and their correlations. The approach yields exact results for a particle on a group manifold and connects to 2D CFTs with Virasoro symmetry, reproducing holographic AdS${}_3$ gravity in the appropriate limit. Overall, the paper provides a microscopic, non-gravitational realization of replica wormholes and a novel thermal mixed state that clarifies how classical correlations, quantum entanglement, and degeneracies contribute to entropy and information flow in wormhole geometries.
Abstract
We introduce a geometric path integral definition of wormhole partition functions in a general class of 1D quantum systems obtained by quantizing a phase space. We compute the wormhole partition function in a semi-classical limit and in some simple examples. The partition function of the n-fold wormhole is found to be identical to the n-th Renyi entropy of a thermal mixed state of the doubled system. This mixed state incorporates three types of quantum statistical behavior: classically correlated, quantum entangled, and classically uncorrelated. We apply our prescription to 2D CFTs with Virasoro symmetry and recover the holographic dual formulation in terms of AdS3 gravity.
