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arXiv · hep-lat/0407034

The Lattice NJL Model at Non-zero Baryon and Isospin Densities

David N. Walters·Simon Hands
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Abstract

We present initial results of a numerical investigation of the chiral symmetry restoring transition in the (3+1)-dimensional Nambu -- Jona-Lasinio model with both non-zero baryon chemical potential (mu_B) and isospin chemical potential (mu_I). With non-zero isospin chemical potential, the model suffers from a sign problem. We proceed in two ways: (i) We perform ``partially quenched'' simulations in which mu_I is made non-zero only during the measurement of chiral observables; (ii) We perform full simulations with imaginary isospin chemical potential with the aim to analytically continue results to real mu_I.

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David N. Walters, Simon Hands. 2004-07-28. The Lattice NJL Model at Non-zero Baryon and Isospin Densities. https://doi.org/10.1016/j.nuclphysbps.2004.11.135

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