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1.
We show that, if one chooses the Einstein static universe as the metric on the conformal boundary of Kerr-anti-de Sitter spacetime, then the Casimir energy of the boundary conformal field theory can easily be determined. The result is independent of the rotation parameters, and the total boundary energy then straightforwardly obeys the first law of thermodynamics. Other choices for the metric on the conformal boundary will give different, more complicated, results. As an application, we calculate the Casimir energy for free self-dual tensor multiplets in six dimensions and compare it with that of the seven-dimensional supergravity dual. They differ by a factor of 5/4.  相似文献   

2.
We analyze the anti-de Sitter/conformal-field-theory dual geometry of an expanding boost-invariant plasma. We show that the requirement of nonsingularity of the dual geometry for leading and subasymptotic times predicts, without any further assumptions about gauge theory dynamics, hydrodynamic expansion of the plasma with viscosity coefficient exactly matching the one obtained earlier in the static case by Policastro, Son, and Starinets.  相似文献   

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In two remarkable recent papers the planar perturbative expansion was proposed for the universal function of the coupling appearing in the dimensions of high-spin operators of the N=4 super Yang-Mills theory. We study numerically the integral equation derived by Beisert, Eden, and Staudacher, which resumes the perturbative series. In a confirmation of the anti-de Sitter-space/conformal-field-theory (AdS/CFT) correspondence, we find a smooth function whose two leading terms at strong coupling match the results obtained for the semiclassical folded string spinning in AdS5. We also make a numerical prediction for the third term in the strong coupling series.  相似文献   

5.
We study the screening length \(L_{\mathrm{max}}\) of a moving quark–antiquark pair in a hot plasma, which lives in a two sphere, \(S^2\), using the AdS/CFT correspondence in which the corresponding background metric is the four-dimensional Schwarzschild–AdS black hole. The geodesic of both ends of the string at the boundary, interpreted as the quark–antiquark pair, is given by a stationary motion in the equatorial plane by which the separation length L of both ends of the string is parallel to the angular velocity \(\omega \). The screening length and total energy H of the quark–antiquark pair are computed numerically and show that the plots are bounded from below by some functions related to the momentum transfer \(P_c\) of the drag force configuration. We compare the result by computing the screening length in the reference frame of the moving quark–antiquark pair, in which the background metrics are “Boost-AdS” and Kerr–AdS black holes. Comparing both black holes, we argue that the mass parameters \(M_{\mathrm{Sch}}\) of the Schwarzschild–AdS black hole and \(M_{\mathrm{Kerr}}\) of the Kerr–AdS black hole are related at high temperature by \(M_{\mathrm{Kerr}}=M_{\mathrm{Sch}}(1-a^2l^2)^{3/2}\), where a is the angular momentum parameter and l is the AdS curvature.  相似文献   

6.
A recent proposal by Ryu and Takayanagi for a holographic interpretation of entanglement entropy in conformal field theories dual to supergravity on anti-de Sitter space is generalized to include entanglement entropy of black holes living on the boundary of anti-de Sitter space. The generalized proposal is verified in boundary dimensions d=2 and d=4 for both the uv-divergent and uv-finite terms. In dimension d=4 an expansion of entanglement entropy in terms of size L of the subsystem outside the black hole is considered. A new term in the entropy of dual strongly coupled conformal-field theory, which universally grows as L(2)lnL and is proportional to the value of the obstruction tensor at the black hole horizon, is predicted.  相似文献   

7.
We show that the quantum universe emerging from a nonperturbative, Lorentzian sum over geometries can be described with a high accuracy by a four-dimensional de Sitter spacetime. By a scaling analysis involving Newton's constant, we establish that the linear size of the quantum universes under study is in between 17 and 28 Planck lengths. Somewhat surprisingly, the measured quantum fluctuations around the de Sitter universe in this regime are to good approximation still describable semiclassically. The numerical evidence presented comes from a regularization of quantum gravity in terms of causal dynamical triangulations.  相似文献   

8.
An extension of the Parikh-Wilczek's semi-classical quantum tunneling method, the tunneling radiation of the charged particle from a torus-like black hole is investigated. Difference from the uncharged mass-less particle, the geodesics of the charged massive particle tunneling from the black hole is not light-like, but determined by the phase velocity. The derived result shows that the tunneling rate depends on the emitted particle's energy and electric charge, and takes the same functional form as uncharged particle. It proves also that the exact emission spectrum is not strictly pure thermal, but is consistent with the underlying unitary theory. PACS Numbers: 04.70.Dy, 97.60.Lf, 05.30.Ch.  相似文献   

9.
Electron mobilities in PbS at a lattice temperature of 77°K have been calculated by the Monte Carlo method. The effects of the band nonparabolicity and of the deformation potential acoustic and polar optical phonon scattering have been included in the calculations. The results are compared with experiments and with the ones obtained on the basis of a displaced Maxwellian distribution function.  相似文献   

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We analyze noncommutative deformations of a higher dimensional anti-de Sitter-Einstein-Born-Infeld black hole. Two models based on noncommutative inspired distributions of mass and charge are discussed and their thermodynamical properties such as the equation of state are explicitly calculated. In the (3 + 1)-dimensional case the Gibbs energy function of each model is used to discuss the presence of phase transitions.  相似文献   

12.
D. Lindley 《Nuclear Physics B》1984,236(2):522-546
We give a discussion, based on the ideas of Coleman and de Luccia, of the geometry of bubbles of real vacuum as they appear in a der Sitter universe dominated by false-vacuum energy density. This geometry seems not to be uniquely determined, and it is difficult to find a physical basis for discriminating between the different types of bubble. We also calculate numerically the tunnelling action for bubbles, in the case where false and real vacua are separated by a small barrier. The action is rather small, and varies only in a weak logarithmic way with barrier height, a result which may cause problems for some varieties of the “new” inflationary universe.  相似文献   

13.
The gravitational collapse of a massless scalar field with a self-interaction term λφ~4 in anti-de Sitter space is investigated.We numerically investigate the effect of the self-interaction term on the critical amplitudes,forming time of apparent horizon,stable island,and energy transformation.The results show that a positiveλsuppresses the formation of black hole,while a negativeλenhances the process.We define two susceptibilities to characterize the effect of the self-interaction on the black hole formation,and find that near the critical amplitude,there exists a universal scaling relation with the critical exponentα≈0.74 for the time of black hole formation.  相似文献   

14.
Through the gauge field theory, we obtain the solution of the DBI-AdS black hole. In the meantime, according to the relations between the action and the grand partition function, we obtain the grand partition function in the DBI-AdS black hole. The temperature and the potential of the DBI-AdS black hole are gained from differential of the grand partition function. With the thermodynamic relations, other thermodynamics are also obtained. The solution and the thermodynamics of the DBI-AdS black hole are turned out that they can reduce to the case of a charged black hole in four-dimensional spacetimes.  相似文献   

15.
The behavior of neutrinos as particles with spin 1/2 and with a strictly zero rest mass is studied. The qualitative differences between the case in which a particle's mass is small and that in which it is strictly zero are considered. In the former, a spin-1/2 particle must be described by a spinor, while in the latter, it can be described by a semispinor. These differences are manifested not only at the quantum but also at the classical level. It is essential that the case of a particle with a zero rest mass must be treated as strictly relativistic at any level. The exclusive properties of isotropic geodesic lines are considered. The chief one is their inherent conformal invariance. Because of it, the conformal angular momentum of a particle with zero rest mass is conserved in a Riemann universe that admits of a continuous group of conformal transformations. This is a 15-parameter group in a spherical de Sitter universe. Accordingly, 15 linearly independent, conformal momenta are conserved in it. The exclusive properties of isotropic geodesics in a spherical de Sitter universe are also manifested in the fact that they are straight in a five-dimensional, pseudo-Euclidean space enveloping that universe. Joint Institute for Nuclear Research. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 114–119, October, 1998.  相似文献   

16.
Electron-positron pair and photon generation from vacuum is considered for a de Sitter space. The amplitude is calculated in the lowest order of perturbation theory with respect to the radiation interaction. The initial and final vacuum states of the quantized spinor field are taken as those of an adiabatic Bunch-Davis vacuum. The amplitude is shown to be zero, i.e., an adiabatic vacuum in a de Sitter space is stable with respect to radiation. Biya Technological Institute, Polzunov Altai State Technological University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 85–89, October, 1998.  相似文献   

17.
Anti-de Sitter时空内柱黑洞的量子熵   总被引:3,自引:0,他引:3       下载免费PDF全文
李固强 《物理学报》2006,55(2):995-998
利用brick-wall方法计算了Anti-de Sitter时空内起源于Dirac场的柱黑洞的量子熵.结果表明,忽略远离围绕系统的真空的贡献时,量子熵包含了线性发散项和对数发散项,整个表达式的形式与标量场的不一样.无论整个对数项还是与自旋联系的子对数项都总是正的. 关键词: brick-wall方法 量子熵 柱黑洞 Dirac场  相似文献   

18.
General features of extended supergravity with a gauge internal symmetry are discussed from a group-theoretical point of view.  相似文献   

19.
The shear viscosity of QED plasma at finite temperature and density is calculated by solving Boltzmann equation with variational approach. The result shows the small chemical potential enhances the viscosity in leading-log order by adding a chemical potential quadratic term to the viscosity for the pure temperature environment. Arrival of the final proofs: 25 November 2005 PACS: 52.25.Fi, 05.20.Dd, 11.10.Wx  相似文献   

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