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arXiv · 2512.09415

Finite density lattice QCD without extrapolations

Alexander Adam·Szabolcs Borsányi·Zoltán Fodor·Jana N. Guenther·Paolo Parotto·Attila Pásztor·Ludovica Pirelli·Chik Him Wong
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Abstract

Finite density lattice QCD usually relies on extrapolations in baryon chemical potential ($\mu_B$), be it Taylor expansion, T' expansion (\cite{Borsanyi:2021sxv}) 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 $\mu_B$. 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 $n_B$ and $n_S$. Our computations rely on high-statistics simulations with 2+1 4HEX-staggered fermions.

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Alexander Adam, Szabolcs Borsányi, Zoltán Fodor, Jana N. Guenther, Paolo Parotto, Attila Pásztor, Ludovica Pirelli, Chik Him Wong. 2025-12-10. Finite density lattice QCD without extrapolations. https://arxiv.org/abs/2512.09415

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