Title: On the binding of two nucleons from lattice QCD
Abstract: Lattice QCD calculations of two- and three-hadron scattering amplitudes are on firm footing from a theoretical standpoint. This has led to the successful extraction of scattering amplitudes for several systems, with most studies involving the scattering of two mesons. However, there have been significant discrepancies between different groups when using these methods to extract the binding energy of two nucleons. Calculations involving baryons are significantly more challenging due to the increased severity of the exponentially decaying signal-to-noise ratio. This issue can lead to a large systematic error in the extraction of multi-hadron finite-volume energies used to constrain the scattering amplitudes. This systematic can be difficult, or impossible, to accurately quantify and likely plays a significant role in the observed discrepancies of the binding energies. With the use of modern lattice calculations and analysis methods, the leading contamination of the finite-volume energies from higher-lying states can be suppressed. All results for the binding of two baryons have been consistent when utilizing these state-of-the-art methods, which have also been in qualitative agreement with an alternative approach for calculating the binding energy called the HAL QCD potential method. In this talk, I will give some historical context on the disagreement in the literature and then present recent results at a pion mass of ∼ 714 MeV which strongly disfavors the binding of two nucleons.