http://arxiv.org/abs/2005.14205
Deconfined quark matter may be present in the cores of massive neutron stars, and is in addition expected to be produced in binary neutron star mergers. While the bulk thermodynamic properties of the medium may undergo only moderate changes at the transition density, transport properties are expected to be qualitatively different in the nuclear and quark matter phases, possibly leading to observable effects. Motivated by recent advances in neutron star observations, we perform the first-ever systematic study of the bulk and shear viscosities as well as the thermal and electrical conductivities in dense unpaired quark matter using holography. Working in the bottom-up V-QCD model and comparing our results to the predictions of a top-down D3-D7 system, we arrive at results that are in qualitative disagreement with the available leading-order predictions from perturbative QCD. Our findings highlight the differing transport properties of weakly and strongly interacting systems, and call for caution in the use of the perturbative results in neutron-star applications.
C. Hoyos, N. Jokela, M. Jarvinen, et. al.
Mon, 1 Jun 20
37/50
Comments: 9 pages, 4 figures