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arXiv · 2606.20090

Hamiltonian-based dimensional reduction and spectral reconstruction with Wilson-Dirac fermions

P. V. Buividovich·B. Hind
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Abstract

Motivated by the process of reconstructing real-time spectral functions from Euclidean correlators in lattice QCD, we derive explicit expressions for the fermionic determinant and the propagator of the four-dimensional clover-improved Wilson-Dirac fermions on anisotropic lattices in terms of the three-dimensional Wilson-Dirac Hamiltonian operator. We derive an effective Hamiltonian that governs Euclidean time evolution at finite temporal lattice spacing, and demonstrate its hermiticity and particle-anti-particle symmetry. Our results allow to quantify lattice artifacts of the numerical spectral reconstruction based on Euclidean fermionic correlators at finite temporal lattice spacing.

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P. V. Buividovich, B. Hind. 2026-06-18. Hamiltonian-based dimensional reduction and spectral reconstruction with Wilson-Dirac fermions. https://arxiv.org/abs/2606.20090

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