programming
Apr 25, 2026 · 21 min Locality, all the way up to the spectrum
> **Paper:** *Subsystem-Resolved Spectral Theory for Quantum Many-Body Hamiltonians* > **Author:** MD Nahidul Hasan Sabit > **arXiv:** [2604.21929](https://arxiv.org/abs/2604.21929) [quant-ph], 2026
— locality lifts to the spectrum, exactly when we want