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Least Action Principle for the Real-Time Density Matrix Renormalization Group

Kouji Ueda·Chenglong Jin·Naokazu Shibata·Yasuhiro Hieida·Tomotoshi Nishino
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Abstract

A kind of least action principle is introduced for the discrete time evolution of one-dimensional quantum lattice models. Based on this principle, we obtain an optimal condition for the matrix product states on succeeding time slices generated by the real-time density matrix renormalization group method. This optimization can also be applied to classical simulations of quantum circuits. We discuss the time reversal symmetry in the fully optimized MPS.

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Kouji Ueda, Chenglong Jin, Naokazu Shibata, Yasuhiro Hieida, Tomotoshi Nishino. 2006-12-20. Least Action Principle for the Real-Time Density Matrix Renormalization Group. https://arxiv.org/abs/cond-mat/0612480

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