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arXiv · 2404.14151

Full QCD with milder topological freezing

Claudio Bonanno·Giuseppe Clemente·Massimo D'Elia·Lorenzo Maio·Luca Parente
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Abstract

We simulate $N_f=2+1$ QCD at the physical point combining open and periodic boundary conditions in a parallel tempering framework, following the original proposal by M. Hasenbusch for $2d$ $\mathrm{CP}^{N-1}$ models, which has been recently implemented and widely employed in $4d$ $\mathrm{SU}(N)$ pure Yang-Mills theories too. We show that using this algorithm it is possible to achieve a sizable reduction of the auto-correlation time of the topological charge in dynamical fermions simulations both at zero and finite temperature, allowing to avoid topology freezing down to lattice spacings as fine as $a \sim 0.02$ fm. Therefore, this implementation of the Parallel Tempering on Boundary Conditions algorithm has the potential to substantially push forward the investigation of the QCD vacuum properties by means of lattice simulations.

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Claudio Bonanno, Giuseppe Clemente, Massimo D'Elia, Lorenzo Maio, Luca Parente. 2024-09-02. Full QCD with milder topological freezing. https://arxiv.org/abs/2404.14151

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