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arXiv · 2609.31504

Bound States in 2d Yukawa Theory from Hamiltonian Truncation

Olivier Delouche·Kara Farnsworth·Francesco Riva
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Abstract

We study the spectrum of two-dimensional Yukawa theory using Hamiltonian truncation, with a focus on bound states. We extend the framework of Hamiltonian truncation effective theory to include fermions and logarithmic UV divergences. With these corrections, the energy levels converge as a function of the cutoff with the scaling predicted by power counting. We identify a strategy to follow the evolution of fermion-antifermion bound states from weak to strong coupling, and investigate its binding energy, finding good agreement with finite-volume perturbation theory at weak coupling. Finally, we explore the heavy-scalar regime toward the massive Thirring/Sine-Gordon limit, recovering the expected weak-coupling behavior and outlining how the calculation can be extended toward this limit.

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Olivier Delouche, Kara Farnsworth, Francesco Riva. 2026-09-25. Bound States in 2d Yukawa Theory from Hamiltonian Truncation. https://arxiv.org/abs/2609.31504

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