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arXiv · 2411.15730

Finite-volume quantization condition from the $N/D$ representation

Sebastian M. Dawid·Andrew W. Jackura·Adam P. Szczepaniak
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Abstract

We propose a new model-independent method for determining hadronic resonances from lattice QCD. The formalism is derived from the general principles of unitarity and analyticity, as encoded in the $N/D$ representation of a partial-wave two-body amplitude. The associated quantization condition relates the finite-volume spectrum to the infinite-volume numerator, $\mathcal{N}$, used to reconstruct the scattering amplitude from dispersive relations. Unlike the original L\"uscher condition, this new formalism is valid for energies coinciding with the left-hand cuts from arbitrary one- and multi-particle exchanges.

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Sebastian M. Dawid, Andrew W. Jackura, Adam P. Szczepaniak. 2024-11-24. Finite-volume quantization condition from the $N/D$ representation. https://arxiv.org/abs/2411.15730

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