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arXiv · 2604.04778

QCommute: a tool for symbolic computation of nested commutators in quantum many-body spin-1/2 systems

Oleg Lychkovskiy·Viacheslav Khrushchev·Ilya Shirokov
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Abstract

We present QCommute, a software tool implemented in C++ for symbolic computation of nested commutators between a Hamiltonian and local observables in quantum many-body spin-1/2 systems on one-, two-, and three-dimensional hypercubic lattices. The computation is performed algebraically directly in the thermodynamic limit, and the Hamiltonian parameters are kept symbolic. Importantly, this way the entire parameter space is covered in a single run. The implementation supports extensive parallelization to achieve high computational performance. QCommute can serve as a computational backend for Heisenberg-picture approaches to quantum dynamics in strongly correlated regimes, ranging from direct Taylor expansion in time to advanced techniques such as the recursion method.

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Oleg Lychkovskiy, Viacheslav Khrushchev, Ilya Shirokov. 2026-04-06. QCommute: a tool for symbolic computation of nested commutators in quantum many-body spin-1/2 systems. https://arxiv.org/abs/2604.04778

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