quant-phAug 22, 2026

Scalable quantum simulation of continuous-time generative models via tensor networks

Authors: Nathan X. Kodama, L. Andrew Wray, Sam Cochran, Chad Rigetti, Shravan Veerapaneni, Michael J. Keiser

Organizations: Sygaldry Technologies, Inc., Ann Arbor, MI, USA. · University of Michigan, Ann Arbor, MI, USA.

Abstract

Continuous-time flow and diffusion models are widely used across many application domains, from large-scale deployment in computer vision and protein folding to emerging adoption for modeling language, time series, and quantum states. After training, inferring statistical properties from continuous-time models is costly. Wavefunction flows target this cost by recasting learned transport as unitary evolution, whose final Born distribution approximates the target distribution. This prepares a coherent amplitude encoding (a qsample) that can be post-processed by quantum algorithms offering a quadratic advantage over Monte Carlo sampling. We present the first numerical study of these flows, in which we represent time-dependent potentials and states as tensor networks. At spatial dimension d=8d=8, storage falls by ∼107×\sim 10^7\times relative to the dense grid of NdN^d points, and evolution wall-clock time falls by ≳103×\gtrsim 10^3\times against a baseline extrapolated from the measured d≤5d\le 5 scaling. We validate our pipeline by reproducing the O(1/prare)O(1/\sqrt{p_{\rm rare}}) scaling of rare-event sampling.

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