Speaker
Description
We propose a universality-based reconstruction of the QCD chiral crossover line from Lee--Yang edge singularities in the complex baryon chemical potential plane[1]. The framework maps lattice-extracted complex Lee--Yang-zero estimates, treated as proxies for edge singularities, to the universal chiral Lee--Yang edge and thereby determines the $\mu_B$ dependence of both the chiral critical line in the light-quark chiral limit and the pseudo-critical crossover line at physical quark masses. As an illustration, we apply the framework to Lee--Yang-zero estimates recently obtained by the Wuppertal--Budapest collaboration from high-statistics lattice QCD simulations. Without imposing the previously determined small-$\mu_B$ expansion of the crossover line as input, the reconstructed curvature is consistent with existing continuum lattice-QCD results at small $\mu_B$. The fitted chiral-limit transition temperature is also compatible with existing chiral-scaling analyses. These results demonstrate that lattice information on Lee--Yang singularities, combined with universal chiral scaling, provides a quantitatively consistent constraint on the QCD crossover line within the present temperature window and establishes a framework that can be systematically improved with future Lee--Yang-zero determinations.
[1] H.-T. Ding, S. Mukherjee, P. Petreczky, and K.-F. Ye, QCD Chiral Crossover Line from Lee-Yang Edge Singularities, arXiv:2608.05752 [hep-lat] (2026).
