Thermodynamic properties of holographic multiquark and the multiquark star

Abstract

We study thermodynamic properties of the multiquark nuclear matter. The dependence of the equation of state on the colour charges is explored both analytically and numerically in the limits where the baryon density is small and large at fixed temperature between the gluon deconfinement and chiral symmetry restoration. The gravitational stability of the hypothetical multiquark stars are discussed using the Tolman-Oppenheimer-Volkoff equation. Since the equations of state of the multiquarks can be well approximated by different power laws for small and large density, the content of the multiquark stars has the core and crust structure. We found that most of the mass of the star comes from the crust region where the density is relatively small. The mass limit of the multiquark star is determined as well as its relation to the star radius. For typical energy density scale of 10 GeV/fm 3 , the converging mass and radius of the hypothetical multiquark star in the limit of large central density are approximately 2.6−3.9 solar mass and 15-27 km. The adiabatic index and sound speed distributions of the multiquark matter in the star are also calculated and discussed. The sound speed never exceeds the speed of light and the multiquark matters are thus compressible even at high density and pressure. *

Stiff phases in strongly coupled gauge theories with holographic duals

“…The holographic approach has already been used to describe both the confined [17][18][19][20][21][22][23][24] and deconfined [25][26][27][28] phases of QCD matter through the study of strongly coupled non-Abelian gauge field theories containing fundamental matter with a global U(1) baryon symmetry. In [27], we adopted the strategy of describing the low-density phase of QCD matter using the Chiral Effective Theory (CET) results of [29], supplemented by the extrapolations provided in [5], and matching them with the EoS of N = 2 Super Yang-Mills theory at finite baryon density, corresponding to a D3-D7 brane intersection on the gravity side.…”

Breaking the sound barrier in holography

“…In this context, a highly promising avenue is the application of the holographic duality [8], which has indeed been lately applied to the description of both the nuclear [9][10][11][12][13][14][15][16] and quark matter [17][18][19] phases inside a neutron star.…”

Massive neutron stars with holographic multiquark cores

“…In this work, we revisit the holographic model investigated in Ref. [7] and match the EoS of multiquark nuclear matter with the low and high density EoS and demonstrate that it can interpolate well between the two regions. The masses of NS with multiquark core are consistent with current observations, allowing NS with M 2M [3,4].…”

“…There are some studies on the holographic model of deconfined quark matter in the dense star e.g. in D3/D7 system [11] and in D4/D8/D8 system [6,7].…”