119431360
Hawking radiation of charged particles as tunneling from higher dimensional Reissner-Nordstrom-de Sitter black holes
Recent work that treats the Hawking radiation as a semi-classical tunnelling process from the four-dimensional Schwarzschild and Reissner-Nordstrom black holes is extended to the case of higher dimensional Reissner-Nordstrom-de Sitter black holes. The result shows that the tunnelling rate is related to the change of Bekenstein-Hawking entropy and the exact radiant spectrum is no longer precisely thermal after considering the black hole background as dynamical and incorporating the self-gravitation effect of the emitted particles when the energy conservation and electric charge conservation are taken into account.
119247463
Extremal Kerr/CFT correspondence of five-dimensional rotating (charged) black holes with squashed horizons
Abstract A new holographic duality named Kerr/CFT correspondence was recently proposed to derive the statistical entropy of four-dimensional extremal Kerr black holes via identifying the quantum states in the near-horizon region with those of two-dimensional conformal field theory living on the boundary. In this paper, we apply this method to investigate five-dimensional extremal Kerr and Cvetic–Youm black holes with squashed horizons in different coordinates and find that the near-horizon geometries are not affected by the squashing transformation. Our investigation shows that the microscopic entropies are in agreement with those given by Bekenstein–Hawking formula. In addition, we have also investigated thermodynamics of the general non-extremal Cvetic–Youm black holes with squashed horizons.
16888502
Anomalies and de Sitter radiation from the generic black holes in de Sitter spaces
Abstract Robinson–Wilczek's recent work shows that, the energy–momentum tensor flux required to cancel gravitational anomaly at the event horizon of a Schwarzschild-type black hole has an equivalent form to that of a ( 1 + 1 ) -dimensional blackbody radiation at the Hawking temperature. Motivated by their work, Hawking radiation from the cosmological horizons of the general Schwarzschild–de Sitter and Kerr–de Sitter black holes, has been studied by the method of anomaly cancellation. The result shows that the absorbing gauge current and energy momentum tensor fluxes required to cancel gauge and gravitational anomalies at the cosmological horizon are precisely equal to those of Hawking radiation from it. It should be emphasized that the effective field theory for generic black holes in de Sitter spaces should be formulated within the region between the event horizon (EH) and the cosmological horizon (CH), to integrate out the classically irrelevant ingoing modes at the EH and the classically irrelevant outgoing modes at the CH, respectively.
119122280
Thermodynamics of five-dimensional static three-charge STU black holes with squashed horizons
Abstract We present a new expression for the five-dimensional static Kaluza–Klein black hole solution with squashed S 3 horizons and three different charge parameters. This black hole solution belongs to D = 5 , N = 2 supergravity theory, its spacetime is locally asymptotically flat and has a spatial infinity R × S 1 ↪ S 2 . The form of the solution is extraordinary simple and permits us very conveniently to calculate its conserved charges by using the counterterm method. It is further shown that our thermodynamical quantities perfectly obey both the differential and the integral first laws of black hole thermodynamics if the length of the compact extra-dimension can be viewed as a thermodynamical variable.
117659024
Hawking Radiation of Photons in a Vaidya–de Sitter Black Hole
Hawking evaporation of photons in a Vaidya–de Sitter black hole is investigated by using the method of generalized tortoise coordinate transformation. Both the location and the temperature of the event horizon depend on the time. It is shown that Hawking radiation of photons exists only for the complex Maxwell scalar φ0 in the advanced Eddington–Finkelstein coordinate system. This asymmetry of Hawking radiation for different components of Maxwell fields probably arises from the asymmetry of spacetime in the advanced Eddington–Finkelstein coordinate system. It is shown that the black body radiant spectrum of photons resembles that of Klein–Gordon particles.
120167831
Hawking Radiation of Charged Particles via Tunneling from Arbitrarily Dimensional Reissner-Nordström Black Holes
Parikh-Wilzcek’s recent work, which treats the Hawking radiation as semi-classical tunneling process from the event horizon of four dimensional Schwarzshild and Reissner- Nordström black hole, indicates that self-gravitation gives a correction to the Hawking precisely thermal spectrum and the tunneling rate is related to the change of Bekenstein- Hawking, but satisfies the underlying unitary theory. In this paper, we extend the model to study the Hawking radiation of charged particles via tunneling from arbitrarily dimensional Reissner-Nordström black holes, and obtain the same result as Parikh-Wilzcek’s. Meanwhile, in this framework, we point out that the first law of the black hole thermodynamics is reliable and the information conservation is only suitable for the reversible process.
10513230
Holographic QCD with topologically charged domain-wall/membranes
We study the thermodynamical phase structures of holographic QCD with nontrivial topologically charged domain-wall/membranes which are originally related to the multiple θ-vacua in the large Nc limit. We realize the topologically charged membranes as the holographic D6-brane fluxes in the Sakai-Sugimoto model. The D6-brane fluxes couple to the probe D8- via Chern-Simon term, and act as the source for the baryonic current density of QCD. We find rich phase structures of the dual meson system by varying asymptotic separation of D8 and . Especially, there can be a thermodynamically favored and stable phase of finite baryonic current density. This provides the supporting evidence for the discovery of the topologically charged membranes found in the lattice QCD calculations. We also find a crossover phase with the limiting baryonic current density and temperature which suggest a Hagedorn-like phase transition of meson dissociation.
121867688
Calibration of a digital hadron calorimeter with muons
The calibration procedure of a finely granulated digital hadron calorimeter with Resistive Plate Chambers as the active elements is described. Results obtained with a stack of nine layers exposed to muons from the Fermilab test beam are presented.
55380857
Mimic the optical conductivity in disordered solids via gauge/gravity duality ✩
Abstract We study the optical conductivity in a ( 2 + 1 ) -dimensional non-relativistic field theory holographically dual to a ( 3 + 1 ) -dimensional charged Lifshitz black brane within the Einstein–Maxwell-dilaton theory. Surprisingly, we find that the optical AC conductivity satisfies the nontrivial (non-)power law scaling in the high frequency regime rather than approaching to a constant when the dynamical critical exponent z > 1 , which is qualitatively similar to those in various disordered solids in condensed matter systems. Besides, this (non-)power law scaling behavior shows some universality, which is robust against the temperatures. We argue that the peculiar scaling behavior of AC conductivity may stem from the couplings of the dilaton field with the gauge fields and also the logarithmic behavior near the boundary in the Lifshitz spacetime.
56229424
Phase structure in a dynamical soft-wall holographic QCD model
A bstractWe consider the Einstein-Maxwell-dilaton system with an arbitrary kinetic gauge function and a dilaton potential. A family of analytic solutions is obtained by the potential reconstruction method. We then study its holographic dual QCD model. The kinetic gauge function can be fixed by requesting the linear Regge spectrum of mesons. We calculate the free energy to obtain the phase diagram of the holographic QCD model and interpret our result as the heavy quarks system by comparing the recent lattice QCD simulation. We finally obtain the equations of state in our model.
119264101
Novel features of the transport coefficients in Lifshitz black branes
We study the transport coefficients, including the conductivities and shear viscosity of the non-relativistic field theory dual to the Lifshitz black brane with multiple U(1) gauge fields by virtue of the gauge/gravity duality. Focusing on the case of double U(1) gauge fields, we systematically investigate the electric, thermal and thermoelectric conductivities for the dual non-relativistic field theory. In the large frequency regime, we find a nontrivial power law behavior in the electric AC conductivity when the dynamical critical exponent z>1 in (2+1)-dimensional field theory. The relations between this novel feature and the `symmetric hopping model' in condensed matter physics are discussed. In addition, we also show that the Kovtun-Starinets-Son bound for the shear viscosity to the entropy density is not violated by the additional U(1) gauge fields and dilaton in the Lifshitz black brane.