Finite density lattice QCD without extrapolations

¹ Department of Physics, Wuppertal University, Gaussstr. 20, D-42119, Wuppertal, Germany
² Department of Physics, Pennsylvania State University, State College, PA 16801, USA
³ Institute for Theoretical Physics, ELTE Eötvös Loránd University, Pázmány P. sétány 1/A, H-1117 Budapest, Hungary
⁴ Jülich Supercomputing Centre, Forschungszentrum Jülich, D-52425 Jülich, Germany
⁵ Dipartimento di Fisica, Università di Torino and INFN Torino, Via P. Giuria 1, I-10125 Torino, Italy

^* e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Published online: 17 April 2026

Abstract

Finite density lattice QCD usually relies on extrapolations in baryon chemical potential (μ_B), be it Taylor expansion, T' expansion ([1]) or analytical continuation. However, their range of validity is difficult to control. In the canonical formulation, the baryon density is the parameter of the system, not μ_B. Here we demonstrate that we can access finite density QCD in the canonical formulation with physical quark masses. We present first results with both the strangeness (n_S ) and baryon (n_B) densities as parameters. Specifically, we compute the QCD pressure and chemical potentials as functions of nB and nS . Our computations rely on high-statistics simulations with 2+1 4HEX-staggered fermions.