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arXiv · 2501.02713

Axial-Vector and Tensor Spin Polarization and Chiral Restoration in Quark Matter

Tomoyuki Maruyama·Toshitaka Tatsumi
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Abstract

We study spontaneous spin-polarizations of quark matter with flavour $SU(2)$ symmetry at zero temperature in the NJL model. In a relativistic framework, there are two types of the spin-spin interactions: axial-vector (AV) and tensor (T), which accordingly give rise to different types of spin-polarized materials. When the spin-spin interaction is sufficiently strong, the spin-polarized phase emerges within a specific density region. As the spin-spin interaction becomes stronger, this phase extends over higher density region beyond the critical density of chiral restoration in normal quark matter. We show that the spin-polarized phase leads to another kind of the spontaneous chiral symmetry breaking phase.

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Tomoyuki Maruyama, Toshitaka Tatsumi. 2025-01-06. Axial-Vector and Tensor Spin Polarization and Chiral Restoration in Quark Matter. https://doi.org/10.3390/sym16121642

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