The Pauli Lightcone: Information-Theoretic Error Mitigation Beyond the Autocorrelation
cs.MS, cs.IT, math.IT, quant-ph
Submitted: 2026-08-26
Updated: 2026-09-19
Comments: Results are independent and no raw data is disclosed. However, one simulation run incorporated noise data provided under a collaboration agreement for a joint publication in preparation. Withdrawing to resolve partners' concerns and delineate research scope. Revised version to follow, showing key findings are geometric properties reproducible with public synthetic noise models
License: http://creativecommons.org/licenses/by/4.0/
The gist: We introduce the wavemap: a spatial portrait of noise effects that assigns each site a per-noise-level arrival delay l γ(v) and cross-entropy loss L γ(v).
Terminology
Abstract
We introduce the wavemap: a spatial portrait of noise effects that assigns each site a per-noise-level arrival delay l γ(v) and cross-entropy loss L γ(v). These observables are exact at the lightcone frontier, where bond dimension χis small and the simulation is most faithful. Eigenvalue analysis of the composed gate-plus-noise Pauli transfer matrices confirms that the studied noise is pure amplitude damping: the spatial propagation pattern is entirely determined by the gate, making the wavemap a model-free noise diagnostic. We apply the multi-product formula (MPF) to recover the noiseless Pauli weight field from the noisy samples, subject to the Lieb-Robinson causal constraint nMPF <= nnl. Fitting time-adaptive coefficients α(t) over the frontier recovers up to 55% of the information loss relative to the best noisy sample, exploiting the fact that the frontier is where truncation error is smallest. On an IBM heavy-hex lattice with heterogeneous hardware noise the method identifies an information-starved regime, pointing to calibrated synthetic noise as the next required experiment.