method-ed

Perform exact diagonalization of many-body quantum Hamiltonians to extract eigenvalues and eigenvectors.

60|92|Updated Apr 30, 2026
One-click install
npx skills add https://github.com/QuantumBFS/quantum.harness --skill method-ed
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: method-ed
Source: https://github.com/QuantumBFS/quantum.harness/tree/main/skills/method-ed
Command: npx skills add https://github.com/QuantumBFS/quantum.harness --skill method-ed

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

This skill provides a rigorous, exact-diagonalization-based oracle for quantum many-body systems, eliminating approximation errors for small-scale clusters and providing a definitive benchmark for approximate methods like DMRG or QMC.

Core Features & Use Cases

  • Full Spectrum Analysis: Compute exact eigenvalues and eigenvectors for scar towers, ETH diagnostics, and level statistics.
  • Dynamics & Thermodynamics: Perform exact real-time quench evolution and finite-temperature calculations using FTLM/TPQ estimators.
  • Use Case: When calibrating a new DMRG model for a Rydberg chain, use this skill to obtain the exact ground state and low-lying spectrum on a small cluster to verify the accuracy of your approximate method.

Quick Start

Use the method-ed skill to perform an exact diagonalization of the Rydberg PXP model on a 20-site chain to extract the full spectrum and level statistics.

Frequently Asked Questions about method-ed

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I perform exact diagonalization of a many-body quantum Hamiltonian to extract eigenvalues?

Perform exact diagonalization of a many-body quantum Hamiltonian by constructing a symmetry-adapted basis and applying sparse matrix solvers to extract exact eigenvalues and eigenvectors. This handles Hilbert space dimensions up to your memory limit.

What is the best way to benchmark approximate methods like DMRG for a small quantum cluster?

The best way to benchmark approximate methods like DMRG is using exact diagonalization as a rigorous oracle. It eliminates approximation errors for small-scale clusters and provides a definitive ground state and low-lying spectrum to verify accuracy.

How do I compute exact real-time quench evolution and finite-temperature estimators for quantum systems?

Compute exact real-time quench evolution and finite-temperature estimators for quantum systems using Krylov time evolution and FTLM/TPQ estimators. This enables precise dynamics and thermodynamics calculations for small-scale quantum systems.

Can I analyze level statistics and ETH diagnostics using exact diagonalization?

Yes, you can analyze level statistics and ETH diagnostics using exact diagonalization. It computes the full spectrum of many-body quantum Hamiltonians, allowing for detailed analysis of scar towers and thermalization properties.

Does exact diagonalization support symmetry-resolved sectors for quantum many-body systems?

Yes, exact diagonalization supports symmetry-resolved sectors for quantum many-body systems. It requires symmetry-adapted basis construction to efficiently manage Hilbert space dimensions within the available memory limit.

What are the limitations of using exact diagonalization for quantum many-body Hamiltonians?

The primary limitation of exact diagonalization is the Hilbert space dimension, which is constrained by your system's memory limit. It is restricted to small-scale quantum systems and requires sparse matrix solvers to manage computational overhead.