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arXiv · 1309.3500

Sign problem and the chiral spiral on the finite-density lattice

Ryutaro Fukuda·Kenji Fukushima·Tomoya Hayata·Yoshimasa Hidaka
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Abstract

We investigate the sign problem of the fermion determinant at finite baryon density in (1+1) dimensions, in which the ground state in the chiral limit should be free from the sign problem by forming a chiral spiral. To confirm it, we evaluate the fermion determinant in the continuum theory at the one-loop level and find that the determinant becomes real as expected. The conventional lattice formulation to implement a chemical potential is, however, not compatible with the spiral transformation. We discuss an alternative of the finite-density formulation and numerically verify the chiral spiral on the finite-density lattice.

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Ryutaro Fukuda, Kenji Fukushima, Tomoya Hayata, Yoshimasa Hidaka. 2013-09-26. Sign problem and the chiral spiral on the finite-density lattice. https://doi.org/10.1103/physrevd.89.014508

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