119219715
Dynamics of tachyon field in spatially curved FRW universe
The dynamics of a tachyon field plus a barotropic fluid is investigated in spatially curved FRW universe. We perform a phase-plane analysis and obtain scaling solutions accompanying with a discussion on their stability. Furthermore, we construct the form of scalar potential which may give rise to stable solutions for spatially open and closed universe separately.
118473731
Some properties of the holographic fermions in an extremal charged dilatonic black hole
We study the properties of the Green's functions of the fermions in the extremal charged dilatonic black hole proposed by Gubser and Rocha [Phys. Rev. D \textbf{81}, 046001 (2010)]. We find that many properties seem to be in agreement with that of Fermi liquid. Especially, the dispersion relation is linear. It is very different from that found in the extremal Reissner-Nordstr$\ddot{o}$m (RN) black hole for massless fermion, which is obviously non-Fermi liquid due to a nonlinear dispersion relation. However, for another scaling behavior of the height of $ImG_{11}$ at the maximum, the scaling exponent is not one, which is at odds with that found in the RN black hole.
121148227
The charged Lifshitz black brane geometry and the bulk dipole coupling
Abstract We study the fermionic response including the bulk dipole coupling on the charged Lifshitz black brane from Einstein–Dilaton–Maxwell model. For fixed Lifshitz dynamical critical exponent z , by tuning the dipole coupling parameter p , we can realize the phase transitions from Fermi liquid, to marginal Fermi liquid, to non-Fermi liquid and finally to Mott insulator. The Lifshitz dynamical critical exponent z plays the role of making the phase transition point from Fermi liquid to non-Fermi liquid or to Mott insulator decrease with the increase of z for fixed dipole coupling p .
118665852
Holographic lattice in Einstein-Maxwell-dilaton gravity
A bstractWe construct an ionic lattice background in the framework of Einstein-Maxwell-dilaton theory in four dimensional space time. The optical conductivity of the dual field theory on the boundary is investigated. Due to the lattice effects, we find the imaginary part of the conductivity is manifestly suppressed in the zero frequency limit, while the DC conductivity approaches a finite value such that the previous delta function reflecting the translation symmetry is absent. Such a behavior can be exactly fit by the Drude law at low frequency. Moreover, we find that the modulus of the optical conductivity exhibits a power-law behavior at intermediate frequency regime. Our results provides further support for the universality of such power-law behavior recently disclosed in Einstein-Maxwell theory by Horowitz, Santos and Tong.
119201080
Holographic fermions in charged Gauss-Bonnet black hole
We study the properties of the Green’s functions of the fermions in charged Gauss-Bonnet black hole. What we want to do is to investigate how the presence of Gauss-Bonnet coupling constant α affects the dispersion relation, which is a characteristic of Fermi or non-Fermi liquid, as well as what properties such a system has, for instance, the Particle-hole (a)symmetry. One important result of this research is that we find for q = 1, the behavior of this system is different from that of the Landau Fermi liquid and so the system can be candidates for holographic dual of generalized non-Fermi liquids. More importantly, the behavior of this system increasingly similar to that of the Landau Fermi liquid when α is approaching its lower bound. Also we find that this system possesses the Particle-hole asymmetry when q ≠ 0, another important characteristic of this system. In addition, we also investigate briefly the cases of the charge dependence.
118494690
The St\"uckelberg Holographic Superconductors in Constant External Magnetic Field
We investigate the St\"{u}ckelberg holographic superconductor in present of the constant external magnetic field. We observe that a critical value of magnetic field exists as the cases in usual holographic superconductor. Furthermore, we find that the applied magnetic field strongly influence the phase transition of this model and have a jump in the condensate at the critical temperature even for $c_{4}=1$.
119236806
Holographic correlation functions for open strings and branes
In this paper, we compute holographically the two-point and three-point functions of giant gravitons with open strings. We consider the maximal giant graviton in S5 and the string configurations corresponding to the ground states of Z = 0 and Y = 0 open spin chain, and the spinning string in AdS5 corresponding to the derivative type impurities in Y = 0 or Z = 0 open spin chain as well. We treat the D-brane and open string contribution separately and find the corresponding D3-brane and string configurations in bulk which connect the composite operators at the AdS5 boundary. We apply a new prescription to treat the string state contribution and find agreements for the two-point functions. For the three-point functions of two giant gravitons with open strings and one certain half-BPS chiral primary operator, we find that the D-brane contributions to structure constant are always vanishing and the open string contribution for the Y = 0 ground state is in perfect match with the prediction in the free field limit.
117894041
Supersymmetric AdS3 × S2 M-theory geometries with fluxes
Motivated by a recent observation that the LLM geometries admit 1/4-BPS M5-brane probes with worldvolume AdS3 × Σ2 × S1 preserving the R-symmetry, SU(2) × U(1), we initiate a classification of the most general AdS3×S2 geometries in M-theory dual to two-dimensional chiral $$ \mathcal{N} = \left( {4,0} \right) $$ SCFTs. We retain all field strengths consistent with symmetry and derive the torsion conditions for the internal six-manifold, M6, in terms of two linearly independent spinors. Surprisingly, we identify three Killing directions for M6, but only two of these generate isometries of the overall ansatz. We show that the existence of this third direction depends on the norm of the spinors. With the torsion conditions derived, we establish the MSW solution as the only solution in the class where M6 is an SU(3)-structure manifold. Then, specialising to the case where the spinors define an SU(2)-structure, we note that supersymmetry dictates that all magnetic fluxes necessarily thread the S2. Finally, by assuming that the two remaining Killing directions are parallel and aligned with one of the two vectors defining the SU(2)-structure, we derive a general relationship for the two spinors before extracting a known class of solutions from the torsion conditions.
15123035
Independent Operators at Different Dimension
To apply lattice QCD in the calculation of glueball spectrum it is needed firstly to know associated operators acting on vacuum. We show how to find all the independent representations and operators, of group $SO(3)^{PC}$ at different dimension, since the work is not trivial. Then, we decompose these representation into irreducible representation of $O^{PC}$ group, which are listed in the note. At last we argue that $f_J(2220)$ and $g_T$ states can not be tensor glueball simultaneously.
119623293
M5-branes and Wilson surfaces
We investigate the M5-brane description of the Wilson surface operators in six-dimensional (2,0) superconformal field theory from AdS/CFT correspondence. We consider the Wilson surface operators in high-dimensional representation, whose description could be M5-brane string soliton solutions in AdS(7) x S' background. We construct such string soliton solutions from the covariant M5-brane equations of motion and discuss their properties. The supersymmetry analysis shows that these solutions are half-BPS. We also discuss the subtle issue on the boundary terms.
119220905
From Liouville to Chern-Simons, Alternative Realization of Wilson Loop Operators in AGT Duality
We propose an SL(2,R) Chern-Simons description of Liouville field theory (LFT), whose correlation function duals to partition function of N=2 SU(2) gauge theories. We give the dual expressions for conformal blocks, fusion rules, and Wilson loop operators in Chern-Simons theory. By realizing Wilson loop operator in Liouville as a Hopf link in S^3 on which lives an SL(2,R) Chern-Simons theory, we obtain an alternative description of monodromy of this loop operator in Liouville field theory as the ratio of link invariants. We show how to calculate t'Hooft loops in the simplest example -- the N=4 super Yang-Mills theory. The results we obtained are consistant with those in 0909.0945 and 0909.1105.