Determine the mass sector without an analytic thermal target
Establish whether the Wetterich flow equation for the finite-temperature $Z_2$-symmetric Higgs–singlet model, supplied with genuine ultraviolet and thermal boundary data but without an analytic one-loop ring-resummed thermal target, can uniquely determine the infrared mass-like combinations and the physically relevant solution branch.
References
Making the flow equation together with the genuine UV and thermal boundary data fix the mass sector on their own, without an analytic thermal target, is in our view the central open problem, ahead of raw network capacity.
— Nonperturbative functional renormalization group for Higgs-singlet models with physics-informed neural networks
(2609.08470 - Yokozaki, 8 Sep 2026) in Section 5.4, “Practical role and limitations of the soft consistency penalty”