Modern Physics Letters A

We review 5D holographic approaches to finite temperature QCD. Thermodynamic properties of the "hard-wall" and the "soft-wall" models are derived. Various non-realistic features in these models are rectified by the setup of improved holographic QCD, that we review here.

Our prediction that the more massive DAMA/LIBRA detector would detect a smaller number of events per unit of mass and time than the DAMA/NaI system has got confirmation. It is easy to understand, because DM objects are by far not the WIMPs of the Galactic halo that interact only weakly with matter but are apparently electrically charged Planckian objects, i.e. daemons which fall from Earth-crossing orbits with V = 30–50 km/s and undergo multiple interaction with condensed matter already in its outer layers, on a path of a few tens of cm. Therefore, one should use not compact massive detectors but rather systems with a large surface area, as we did to detect daemons with thin ZnS(Ag) scintillators. There are grounds to believe that correct use of the single-hit criterion in LIBRA should reveal DM particles with V = 30–50 km/s, and subsequently, with V = 10–15 km/s as well.

A regular solution of the system of coupled equations of the nonlinear electrodynamics and gravity describing static and spherically-symmetric black holes in an asymptotically de Sitter universe is constructed and analyzed. Special emphasis is put on the degenerate configurations (when at least two horizons coincide) and their near horizon geometry. It is explicitly demonstrated that approximating the metric potentials in the region between the horizons by simple functions and making use of a limiting procedure one obtains the solutions constructed from maximally symmetric subspaces with different absolute values of radii. Topologically they are AdS₂×S² for the cold black hole, dS₂×S² when the event and cosmological horizon coincide, and the Plebański–Hacyan solution for the ultraextremal black hole. A physically interesting solution describing the lukewarm black holes is briefly analyzed.

Within the relativistic Hartree approach using a Lagrangian with density-dependent parameters according to the Brown–Rho scaling law, it is found that the vacuum corrections from the nucleon Dirac sea soften the equation of state and favor the chiral symmetry restoration at high densities.

Theoretical consistency of the 3-3-1 model with right-handed neutrinos demands that the number of family of fermions be exactly equal to three. In this brief report we show that such theoretical requirement results in a clean and severe bound on the Z–Z′ mixing angle: -3.979×10^-3<ϕ<1.309×10^-4 with 90% CL.

We present a theoretical approach to the internal motion of a system based on three-body forces among particles in a special case, using three-body potentials. The three-body force models are more easily introduced and treated within the hyperspherical harmonic formalism. The internal particle motion is usually described by means of the Jacobian relative coordinates ρ, λ and R. The problems related to three-body nonhypercentral potentials in three dimensions are investigated. While the difficulties that arise in the study of nonhypercentral potentials are explicitly shown, we discuss some results obtained using nonhypercentral harmonic and anharmonic and some inverse power terms; however the potential can be easily generalized in order to allow a systematic analysis, which presents an exact solution to the wave function. The method is also applied to some other types of potentials.

Recently, it has been suggested that Hawking radiation can be derived from quantum tunneling methods. Here, we calculated Hawking temperature of dilatonic black holes from tunneling formalism. The two semiclassical methods adopted here are: the null-geodesic method proposed by Parikh and Wilczek and the Hamilton–Jacobi method proposed by Angheben et al. We apply the two methods to analyze the Hawking temperature of the static spherical symmetric dilatonic black hole, the rotating Kaluza–Klein black hole, and the rotating Kerr–Sen black hole.

In a recent paper,¹ we missed some components of the contorsion tensor due to the minor error. When we insert the correction and use all the components, the final result becomes more comprehensive. Here we put the corrections and obtain the corresponding results.