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From quarks and gluons to color superconductivity at supranuclear densities

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 نشر من قبل Jens Braun
 تاريخ النشر 2021
  مجال البحث
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We study the emergence of color superconductivity in the theory of the strong interaction at supranuclear densities. To this end, we follow the renormalization group (RG) flow of dense strong-interaction matter with two massless quark flavors from the fundamental quark and gluon degrees of freedom at high energies down to the non-perturbative low-energy regime which is found to be governed by the dynamical formation of diquark states. With the strong coupling at the initial RG scale as the only input parameter, we compute the (chirally symmetric) scalar diquark condensate and analyze its scaling behavior over a wide range of the quark chemical potential. Approximations entering our computations are critically assessed. Since our approach naturally allows us to study the scale dependence of couplings, we also monitor the strength of couplings appearing in low-energy models of dense strong-interaction matter. The observed dependence of these couplings on the quark chemical potential may help to amend model studies in the future.



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