aiqbench analysis
This paper introduces Matrix Product Belief Propagation (MP-BP), a novel algorithm that significantly improves the accuracy of contracting two-dimensional tensor networks and graphical models by quadratically reducing errors. The method effectively bridges classical belief propagation with quantum renormalization group techniques, offering enhanced convergence for both classical and quantum 2D problems at comparable computational costs.
Matrix Product Belief Propagation
arXiv:2609.05598v1 Announce Type: new Abstract: We introduce "matrix product belief propagation" (MP-BP) as a controlled method for the approximate contraction of two-dimensional tensor networks and graphical models, which generically leads to a quadratic reduction of errors relative to existing methods: at similar computational effort, the number of accurate digits is asymptotically doubled. For infinite systems, MP-BP can be understood as a practical implementation of Baxter's corner-transfer-matrix method; for reflection-symmetric networks, it further coincides with the boundary matrix-product-state and corner-transfer-matrix renormalization group algorithms as conventionally implemented. In the limit of unit matrix-product rank, MP-BP is equivalent to belief propagation, and more generally, can be understood as a generalization of BP in which the "messages" live on surfaces and are assumed to have a matrix-product factorization. We further extend the quadratic improvement to the computation of expectation values, and numerically demonstrate the qualitatively improved convergence for a variety of classical and quantum 2D tensor network problems.
Abstract:We introduce "matrix product belief propagation" (MP-BP) as a controlled method for the approximate contraction of two-dimensional tensor networks and graphical models, which generically leads to a quadratic reduction of errors relative to existing methods: at similar computational effort, the number of accurate digits is asymptotically doubled. For infinite systems, MP-BP can be understood as a practical implementation of Baxter's corner-transfer-matrix method; for reflection-symmetric networks, it further coincides with the boundary matrix-product-state and corner-transfer-matrix renormalization group algorithms as conventionally implemented. In the limit of unit matrix-product rank, MP-BP is equivalent to belief propagation, and more generally, can be understood as a generalization of BP in which the "messages" live on surfaces and are assumed to have a matrix-product factorization. We further extend the quadratic improvement to the computation of expectation values, and numerically demonstrate the qualitatively improved convergence for a variety of classical and quantum 2D tensor network problems.
Quantum Physics (quant-ph); Strongly Correlated Electrons (cond-mat.str-el); Computational Physics (physics.comp-ph)
arXiv:2609.05598 [quant-ph]
(or arXiv:2609.05598v1 [quant-ph] for this version)
https://doi.org/10.48550/arXiv.2609.05598 Focus to learn more arXiv-issued DOI via DataCite (pending registration)
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