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arXiv · 2504.07508

Parton Distribution Functions in the Schwinger model from Tensor Network States

Mari Carmen Bañuls·Krzysztof Cichy·C. -J. David Lin·Manuel Schneider
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Abstract

Parton distribution functions (PDFs) describe the inner, non-perturbative structure of hadrons. Their computation involves matrix elements with a Wilson line along a direction on the light cone, posing significant challenges in Euclidean lattice calculations, where the time direction is not directly accessible. We propose implementing the light-front Wilson line within the Hamiltonian formalism using tensor network techniques. The approach is demonstrated in the massive Schwinger model (quantum electrodynamics in 1+1 dimensions), a toy model that shares key features with quantum chromodynamics. We present accurate continuum results for the fermion PDF of the vector meson at varying fermion masses, obtained from first-principle calculations directly in Minkowski space. Our strategy also provides a useful path for quantum simulations and quantum computing.

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Mari Carmen Bañuls, Krzysztof Cichy, C. -J. David Lin, Manuel Schneider. 2026-01-23. Parton Distribution Functions in the Schwinger model from Tensor Network States. https://doi.org/10.1103/lcyh-rxf3

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