2025/05/07 by Fabrizio Murgana, Murgana, Fabrizio, Marco Ruggieri +1
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Lattice (hep-lat) #High Energy Physics - Phenomenology (hep-ph) #High Energy Physics - Theory (hep-th) #High-Energy Particle Collisions Research #Nuclear physics research studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2505.04569
openalex publication_date 2025/05/07 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We test a technique adopted in the lattice simulations framework, to reconstruct the chiral-phase boundary at real chemical potential, μ, via extrapolation from imaginary μ. We use a low-energy effective model, the Quark-Meson model, both in the mean-field approximation and within the Functional Renormalization Group, the latter in the Local Potential Approximation. The model provides results both for real and imaginary values of μ, thus a direct comparison can be performed between the prediction of the model for real values of μ and the ones obtained via extrapolation from the results at imaginary μ. We compute an effective convergence radius for the reconstruction technique, μconv, and find μconv≈146 MeV. This value sustains the validity of the reconstruction technique also for finite and moderate values of the chemical potential. On the other hand, within our model, μconv is quite smaller then the value of μ where we find the actual critical endpoint. Near this point of the phase diagram, we find a discrepancy between the actual phase boundary and the one pbtained via extrapolatin of ≈150%. Therefore, our results show that the location of the critical endpoint obtained via reconstruction from imaginary μ should be considered with due caution