Quantum Many-Body Theory Calculation Application

A comprehensive iOS application for physicists, materials scientists, and researchers working with quantum many-body theory calculations.

Features

1. Keldysh Closed Time Path (CTP) Analysis

• Calculate evolution operators for non-equilibrium quantum systems
• Compute two-point correlation functions
• Analyze time-ordered, retarded, and advanced correlation functions
• Support for custom Hamiltonian and operator inputs

2. Non-Equilibrium Green's Functions

• Calculate lesser, greater, retarded, and advanced Green's functions
• Compute Keldysh Green's functions
• Fourier transform between time and frequency domains
• Visualize Green's functions in both time and frequency representations

3. Quantum Master Equation Solver

• Solve Lindblad master equation for open quantum systems
• Numerical integration using Runge-Kutta 4th order method
• Calculate density matrix evolution
• Compute purity and von Neumann entropy
• Support for multiple Lindblad operators

4. Fluctuation-Dissipation Theorem Verification

• Verify quantum fluctuation-dissipation relations
• Calculate response functions (susceptibility)
• Compute correlation function spectra
• Compare response and correlation functions according to FDT

5. Open Quantum System Analysis

• Study system-environment coupling effects
• Calculate decoherence time (T2)
• Calculate relaxation time (T1)
• Analyze quantum fidelity decay
• Compute entanglement evolution using concurrence