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arXiv · cond-mat/9610107

Density Matrix and Renormalization for Classical Lattice Models

T. Nishino·K. Okunishi
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Abstract

We review the variational principle in the density matrix renormalization group (DMRG) method, which maximizes an approximate partition function within a restricted degrees of freedom; at zero temperature, DMRG mini- mizes the ground state energy. The variational principle is applied to two-dimensional (2D) classical lattice models, where the density matrix is expressed as a product of corner transfer matrices. (CTMs) DMRG related fields and future directions of DMRG are briefly discussed.

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T. Nishino, K. Okunishi. 1996-10-14. Density Matrix and Renormalization for Classical Lattice Models. https://doi.org/10.1007/bfb0104638

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