I built a framework that detects eavesdroppers on quantum key distribution channels by reading the scrambling "fingerprint" embedded in the QBER error timeline, no new hardware required.
The core idea: every QKD channel has a unique Lanczos coefficient sequence derived from its Hamiltonian. An eavesdropper perturbs the Hamiltonian, which shifts the coefficients in a detectable and unforgeable way (Krylov distortion ΔK). Validated on 181,606 experimental QBER measurements from a deployed fiber-optic system, AUC = 0.981.
Based on a 12-paper Zenodo preprint series covering the full theoretical stack: Physical Bridge proof, one-way function property, universality across 8 Hamiltonian families, open-system extension via Lindblad, and Loschmidt echo validation.
Paper series: https://zenodo.org/records/18940281`
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