pyqcmlisted

Assists with pyqcm, the Python/C++ library for quantum cluster methods (CPT, VCA, CDMFT) used to study strongly correlated electron models like the Hubbard model. Use this whenever the user is writing or debugging a pyqcm script (defining clusters, lattice models, operators, parameters, running model_instance calculations), interpreting pyqcm output (spectral functions, Green's functions, self-energy, order parameters, ground state averages, phase diagrams), or reading/modifying the pyqcm source itself (the src_ed exact-diagonalization solver, the src_qcm lattice/CPT-VCA-CDMFT engine, or the src_python nanobind bindings). Also trigger on mentions of cluster perturbation theory, exact diagonalization impurity solver, Lanczos, Lehmann representation, or the qcm_wed/pyqcm-project repository, even if the user doesn't say "pyqcm" by name.
pyqcm-project/pyqcm-skill · ★ 0 · AI & Automation · score 60

Install: claude install-skill pyqcm-project/pyqcm-skill

# pyqcm Pyqcm implements three related quantum cluster methods — Cluster Perturbation Theory (CPT), the Variational Cluster Approach (VCA), and Cellular/Cluster Dynamical Mean Field Theory (CDMFT) — for approximating the physics of strongly correlated (Hubbard-like) lattice models. The impurity solver is exact diagonalization (Lanczos and variants) on sparse matrices. Core numerics are C++; the day-to-day interface is Python. This skill covers three distinct jobs. Figure out which one the user needs (often more than one at once — e.g. debugging a script *and* interpreting why the physics looks wrong) and read the matching reference file before acting: | Job | When | Read | |---|---|---| | Write or debug a pyqcm script | Defining clusters/models/operators, running ED/CDMFT/VCA, fixing a traceback, choosing sectors | `references/scripting.md` | | Interpret physics results | Explaining a spectral function, self-energy, order parameter, or phase diagram; connecting output to the underlying theory | `references/physics.md` | | Modify pyqcm itself | Touching `src_ed/`, `src_qcm/`, `src_python/`, or the pure-Python `pyqcm/*.py` wrapper | `references/contributing.md` | **Always check `references/gotchas.md` first**, regardless of which job it is. It's a running list of hard-won lessons from this specific research group about pyqcm's sharp edges — conventions, past mistakes, build quirks — that aren't written down anywhere else. If you learn a new one during a session (a mistake y