Chiral EFT: New Perspectives
March 17 - 21, 2025
Vincenzo Cirigliano, Thomas Papenbrock, Maria Piarulli, Ubirajara van Kolck
The workshop congregated a relatively small but dynamic set of participants to confront the renormalization, power-counting, and convergence problems faced by nuclear Chiral Effective Field Theory (EFT). Despite the phenomenological successes of chiral potentials, the need to resolve these problems for applications such as tests of fundamental symmetries and astrophysical processes was emphasized. Progress was achieved during the workshop on several fronts. With Bayesian methods, EFT convergence was shown to be tied to renormalization. A renormalizable formulation of Chiral EFT with nonperturbative pions could accommodate the stability of nuclei beyond the alpha particle at leading order, and the importance of novel three-body forces in dense environments was demonstrated. Issues in the renormalization of subleading corrections were addressed. Improvements in power counting were suggested with perturbative pions, unitarity, change in the structure and ordering of short-range forces, delta isobars, and a harmonic-oscillator basis. It emerged that future progress hinges on the extension of many-body methods to accommodate the hierarchy of EFT interactions, with significant achievements reported during the meeting.