Claim record · edition 0.1.0

tn-004Established result

Tensor-network accuracy is controlled by singular-value truncation, and the discarded weight is the quantity that makes a result interpretable.

Each bond is reduced to its D largest singular values; the discarded tail is a measurable error. A result reported without its bond dimension and discarded weight cannot be assessed.

Limits of this claim

Small per-step discarded weight does not bound global error in general. Truncations accumulate, and a sweep can converge cleanly onto a state that the truncation put out of reach.

Supporting sources

review article · identifier verified

The density-matrix renormalization group in the age of matrix product states

Ulrich Schollwöck · 2010

arXiv:1008.3477

Standard reference for MPS canonical forms, SVD truncation, and the reformulation of DMRG in tensor-network language.

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primary paper · identifier verified

Efficient classical simulation of slightly entangled quantum computations

Guifré Vidal · 2003

arXiv:quant-ph/0301063

Ties classical simulation cost to the entanglement carried across a cut, which is the quantity a bond dimension budgets.

Source record →

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