Title: To bind or not to bind? Â A tale of two nucleons
Abstract: Understanding the emergence of nuclear physics from the Standard Model is important for both low-energy precision tests of the Standard Model as well as understanding multi-nucleon forces which are difficult to constrain from experimental information alone. Â Lattice QCD provides us with the only means to directly determine the properties and interactions of nucleons directly from the underlying quark and gluon degrees of freedom, with controlled theoretical uncertainties. Â While lattice QCD calculations of single nucleon properties have now reached percent level control, our ability to understand two-nucleon interactions has been hindered by the multi-scale nature of nuclear interactions. Â Over the last 15 years or so, a controversy emerged on whether or not two nucleons bind at heavy pion mass. Â Resolving this controversy is important to gain confidence in lattice QCD calculations of two nucleon systems and relevant electroweak matrix elements as the issue is a symptom of uncontrolled systematic uncertainties. Â I will present modern lattice QCD calculations that largely resolve this discrepancy.