Stiff phases in strongly coupled gauge theories with holographic duals

We study dense nuclear and quark matter within a single microscopic approach, namely the holographic Sakai-Sugimoto model. Nuclear matter is described via instantons in the bulk, and we show that instanton interactions are crucial for a continuous connection of chirally broken and chirally symmetric phases. The continuous path from nuclear to quark matter includes metastable and unstable stationary points of the potential, while the actual chiral phase transition remains of first order, as in earlier approximations. We show that the model parameters can be chosen to reproduce low-density properties of nuclear matter and observe a non-monotonic behavior of the speed of sound as a function of the baryon chemical potential, as suggested by constraints from QCD and astrophysics.

Section: Speed Of Soundmentioning

confidence: 99%

Towards a holographic quark-hadron continuity

Fadafan

Kazemian

Schmitt

2019

“…The applications of the gauge/gravity duality to quark-gluon plasma has been a very active field [1,2]. Very recently these techniques have also been applied in the context of neutron stars [3,4] and stiff phases of matter [5,6] which are likely to be needed to achieve large enough stars [7]. In [4], a holographic model dual to N = 4 super-Yang-Mills and quenched supersymmetric matter was studied, and it was observed that neutron stars can only accommodate very small amounts of quark matter.…”

Section: Introductionmentioning

confidence: 99%

Holographic QCD in the Veneziano limit and neutron stars

Jokela

Järvinen

Remes

2019

Self Cite

155

We use the holographic V-QCD models to analyse the physics of dense QCD and neutron stars. Accommodating lattice results for thermodynamics of QCD enables us to make generic predictions for the Equation of State (EoS) of the quark matter phase in the cold and dense regime. We demonstrate that the resulting pressure in V-QCD matches well with a family of neutron-star-matter EoSs that interpolate between state-of-the-art theoretical results for low and high density QCD. After implementing the astrophysical constraints, i.e., the largest known neutron star mass and the recent LIGO/Virgo results for the tidal deformability, we analyse the phase transition between the baryonic and quark matter phases. We find that the baryon density n B at the transition is at least 2.9 times the nuclear saturation density n s . The transition is of strongly first order at low and intermediate densities, i.e., for n B /n s 7.5.

“…In [58] it was demonstrated that the original D3-brane background (the dual to N = 4 SYM theory), supplemented with flavor D7-brane probes (introducing quenched quark matter) at finite chemical potential, provides a realistic equation of state for cold and dense quark matter. This realization paved the road for further investigations [59][60][61][62].…”

Section: Discussionmentioning

confidence: 82%

Gravity dual of a multilayer system

Jokela

Penín

Ramallo

et al. 2019

Self Cite

We construct a gravity dual to a system with multiple (2 + 1)-dimensional layers in a (3 + 1)-dimensional ambient theory. Following a top-down approach, we generate a geometry corresponding to the intersection of D3-and D5-branes along 2+1 dimensions. The D5-branes create a codimension one defect in the worldvolume of the D3-branes and are homogeneously distributed along the directions orthogonal to the defect. We solve the fully backreacted ten-dimensional supergravity equations of motion with smeared D5-brane sources. The solution is supersymmetric, has an intrinsic mass scale, and exhibits anisotropy at short distances in the gauge theory directions. We illustrate the running behavior in several observables, such as Wilson loops, entanglement entropy, and within thermodynamics of probe branes.