Kerr/CFT对应在Dilatonic黑洞中的应用

全息原理认为一个量子引力系统的自由度可以完全由其边界上的自由度所描述．AdS／CFT（Antide—SitterSpace／Conforreal Field Theory）对应是全息原理在弦理论中的严格实现，它为我们研究强耦合场论提供了一个强有力的工具．

Joule-Thomson expansion of charged dilatonic black holes

Based on the Einstein-Maxwell theory,the Joule-Thomson(J-T)expansion of charged dilatonic black holes(the solutions are neither flat nor AdS)in(n+1)-dimensional spacetime is studied herein.To this end,we analyze the effects of the dimension n and dilaton fieldαon J-T expansion.An explicit expression for the J-T coefficient is derived,and consequently,a negative heat capacity is found to lead to a cooling process.In contrast to its effect on the dimension,the inversion curve decreases with charge Q at low pressures,whereas the opposite effect is observed at high pressures.We can observe that with an increase in the dimension n or parameter a,both the pressure cut-off point and the minimum inversion temperature T_(min)change.Moreover,we analyze the ratio T_(min)/T_(c)numerically and discover that the ratio is independent of charge;however,it depends on the dilaton field and dimension:for n=3 andα=0,the ratio is 1/2.The dilaton field is found to enhance the ratio.In addition,we identify the cooling-heating regions by investigating the inversion and isenthalpic curves,and the behavior of the minimum inversion mass M_(min)indicates that this cooling-heating transition may not occur under certain special conditions.

Dilaton-Maxwell黑洞的量子隧穿辐射(英文)

对静态球对称的Dilaton-Maxwell黑洞霍金辐射的隧穿过程进行了简单直接的推导,因为推导过程中强调了能量守恒定律,故精确的辐射谱不再是纯热的.当考虑特殊情况时,所得的结果与已知的Schwarzschild隧穿辐射谱一致.

Teleparallel equivalent theory of (1+1)-dimensional gravity

A theory of （1＋1）-dimensional gravity is constructed on the basis of the teleparallel equivalent of general relativity. The fundamental field variables are the tetrad fields ei^μ and the gravity is attributed to the torsion. A dilatonic spherically symmetric exact solution of the gravitational field equations characterized by two parameters M and Q is derived. The energy associated with this solution is calculated using the two-dimensional gravitational energy- momentum formula.

Garfinkle-Horowitz-Stromingen dilaton黑洞的Hawking隧穿辐射

用量子隧穿法研究Garfinkle-Horowitz-Stromingen dilaton黑洞的Hawking辐射,得到了静止质量为零和不为零的两类粒子穿过黑洞事件视界的出射率,发现粒子的量子隧穿辐射谱与黑洞的Bekenstein-Hawking熵变有关,辐射谱不再是严格的纯热谱.

稳态轴对称Sen黑洞的量子效应

借助乌龟坐标，得到了在稳态轴对称Ｓｅｎ黑洞视界附近的Ｋｌｅｉｎ－Ｇｏｒｄｏｎ方程的解，导出了Ｈａｗｋｉｎｇ热谱公式．通过与一般Ｅｉｎｓｔｅｉｎ黑洞比较，发现ｄｉｌａｔｏｎ场对黑洞的热力学性质有很大的影响．

新广义Tortiose坐标变换下动态Dilaton-Maxwell黑洞时空中的非热辐射研究

作者通过哈密顿-雅克比方程,在新乌龟坐标变换下,研究了Dilaton-Maxwell黑洞时空中的非热辐射特征,获得粒子能量所在的禁区宽度,以及出射粒子的最大能量.同时,根据方法我们还得出了该黑洞时空视界处的表面引力.

Abbott-Deser-Tekin Charge of Dilaton Black Holes with Squashed Horizons

We consider the conserved charge of static black holes with squashed horizons in the Einstein-Maxwell-dilaton theory via both the Abbott-Deser-Tekin （ADT） method and its off-shell generalization. We first make use of the original ADT method to compute the mass of the dilaton squashed black holes in terms of three different reference spacetimes, which are the asymptotic geometry, the flat background and the spacetime of the Kaluza- Klein monopole with boundary matched to the original metric, respectively. Each mass satisfies the first law of black hole thermodynamics, although the mass computed on the basis of the boundary matching the Kaluza- Klein monopole is different from that of the other two reference spacetimes. Then the mass of the black holes is evaluated through the off-shell generalized ADT method.

Examining a Fifth Force Application by Using Dilaton Model and Padmanabhan Inflaton Scalar Field in Early Universe to Generate GW and Gravitons

On page 17 of a book on Modified Gravity by Li and Koyama, there is a discussion of how to obtain a Fifth force by an allegedly non-relativistic approximation with a force proportional to minus the spatial derivative of a scalar field. If the scalar field says for an inflaton, as presented by Padmanabhan only depends upon time, of course, this means that no scalar field contributing to a fifth force our proposal in the neighborhood of Planck time is to turn the time into being equal to r/[constant times c]. This is in the neighborhood of Planck time. Then having done that, consider the initially Plank regime inflaton field as being spatially varying and from there apply a fifth force as a way to help initiate black hole production and possibly Gravitons.

On the Dynamical 4D BTZ Black Hole Solution in Conformally Invariant Gravity

We review the (2 + 1)-dimensional Baňados-Teitelboim-Zanelli black hole solution in conformally invariant gravity, uplifted to (3 + 1)-dimensional spacetime. For the matter content we use a scalar-gauge field. The metric is written as where the dilaton field ω contains all the scale dependencies and where represents the “un-physical” spacetime. A numerical solution is presented and shows how the dilaton can be treated on equal footing with the scalar field. The location of the apparent horizon and ergo-surface depends critically on the parameters and initial values of the model. It is not a hard task to find suitable initial parameters in order to obtain a regular and singular free out of a BTZ-type solution for . In the vacuum situation, an exact time-dependent solution in the Eddington-Finkelstein coordinates is found, which is valid for the (2 + 1)-dimensional BTZ spacetime as well as for the uplifted (3 + 1)-dimensional BTZ spacetime. While resembles the standard BTZ solution with its horizons, is flat. The dilaton field becomes an infinitesimal renormalizable quantum field, which switches on and off Hawking radiation. This solution can be used to investigate the small distance scale of the model and the black hole complementarity issues. It can also be used to describe the problem of how to map the quantum states of the outgoing radiation as seen by a distant observer and the ingoing by a local observer in a one-to-one way. The two observers will use a different conformal gauge. A possible connection is made with the antipodal identification and unitarity issues. This research shows the power of conformally invariant gravity and can be applied to bridge the gap between general relativity and quantum field theory in the vicinity of the horizons of black holes.

Relating Some Nonlinear Systems to a Cold Plasma Magnetoacoustic System

Using a Gurevich-Krylov solution that describes the propagation of nonlinear magnetoacoustic waves in a cold plasma, we construct solutions of various other nonlinear systems. These include, for example, Madelung fluid, reaction diffusion, Broer-Kaup, Boussinesq, and Hamilton-Jacobi-Bellman systems. We also construct dilaton field solutions for a Jackiw-Teitelboim black hole with a negative cosmological constant. The black hole metric corresponds to a cold plasma metric by way of a change of variables, and the plasma dilatons and cosmological constant also have an expression in terms of parameters occurring in the Gurevich-Krylov solution. A dispersion relation, moreover, links the magnetoacoustic system and a resonance nonlinear Schrödinger equation.

Consequences of Rényi entropy on the thermal geometries and Hawking evaporation of topological dyonic dilaton black hole

The thermodynamics of black holes(BHs)has had a profound impact on theoretical physics,providing insight into the nature of gravity,the quantum structure of spacetime and the fundamental laws governing the Universe.In this study,we investigate thermal geometries and Hawking evaporation of the recently proposed topological dyonic dilaton BH in anti-de Sitter(Ad S)space.We consider Rényi entropy and obtain the relations for pressure,heat capacity and Gibbs free energy and observe that the Rényi parameter and dilaton field play a vital role in the phase transition and stability of the BH.Moreover,we use Weinhold,Ruppeiner and Hendi Panahiyah Eslam Momennia models to evaluate the scalar curvature of the BH and find out that the divergence points of the scalar curvature coincides with the zero of specific heat.Finally,using Stefan–Boltzmann law,we determine that the BH without a dilaton field evaporates far more quickly compared to the dilaton BH in Ad S space.

95 GeV light Higgs in the top-pair-associated diphoton channel at the LHC in the minimal dilaton model

Motivated by experimental hints and theoretical frameworks indicating the existence of an extended Higgs sector,we explore the feasibility of detecting a 95 GeV light Higgs boson decaying into a diphoton within the minimal dilaton model at the 14 TeV LHC.Initially,we identify the correlations between the production cross section,decay branching ratios,and model parameters,e.g.,the scalar mixing angle■Subsequently,we utilize Monte Carlo simulations to generate the signal of the light Higgs boson via the■process,along with the corresponding backgrounds.To effectively separate the signal from the dominant backgrounds■,we employ a meticulous cut-based selection process.Ultimately,we find that with an integrated luminosity of■,the regions of■can be covered over the3σlevel.

二维Dilaton引力模型中的带电Sine-Gordon孤子解

获得了二维dilaton引力模型中的周期解 ,通过坐标变换证明了周期解和带电sine

Horowitz-Strominger Dilaton黑洞的费米子隧穿

基于Kerner和Mann最近的工作,研究了Horowitz-Strominger Dilaton黑洞膜上的费米子隧穿.由于电磁场将会和物质场和引力场耦合,引入了带电粒子的Dirac方程,由此得到了期待的辐射温度.在考虑自引力相互作用后,发现和标量粒子一样,费米子的隧穿率也满足潜在的幺正原理.

非对易时空下Gibbons-Maeda dilaton黑洞和Garfinkle-Horowitz-Strominger dilaton黑洞的热力学性质

以Gibbons-Maeda dilaton黑洞和Garfinkle-Horowitz-Strominger dilaton黑洞为例,研究空间的非对易性对黑洞热力学性质的影响.通过对比对易时空中Gibbons-Maeda dilaton黑洞和非对易时空中Garfinkle-Horowitz-Strominger dilaton黑洞的温度,得出如下结论:从对黑洞热力学性质产生影响这一角度来说,时空的非对易性和黑洞的荷(电荷或磁荷)有相似的作用.

A light scalar in the Minimal Dilaton Model in light of the LHC constraints

Whether an additional light scalar exists is an interesting topic in particle physics beyond the Standard Model(SM), as we do not know as yet the nature of physics beyond the SM in the low mass region in view of the inconsistent results of the ATLAS and CMS collaborations in their search for light resonances around 95 GeV in the diphoton channel. We study a light scalar in the Minimal Dilaton Model(MDM). Under the theoretical and the latest experimental constraints, we sort the selected data samples into two scenarios according to the diphoton rate of the light scalar: the large-diphoton scenario(with σ_(γγ)/SM■0.2) and the small-diphoton scenario(with σ_(γγ)/SM■0.2),which are favored by the CMS and ATLAS results, respectively. We compare the two scenarios, test the characteristics of the model parameters, the scalar couplings, production and decay, and consider how they could be further discerned at colliders. We draw the following conclusions for the two scenarios:(i) The large-diphoton scenario has in general a small Higgs-dilaton mixing angle(|sinθ_S|■0.2) and a small dilaton vacuum expectation value(VEV)f(0.5■η≡ v/f■1),and the small-diphoton scenario has large mixing(| sinθ_S|■0.4) or large VEV(η≡v/f ■0.3).(ii) The large-diphoton scenario in general predicts small syy coupling(|C_(sγγ)/SM|■ 0.3) and large sgg coupling(0.6■|C_(sgg)/SM|■1.2), while the small-diphoton scenario predicts small sgg coupling(|C_(sgg)/SM|■0.5).(iii) The large-diphoton scenario can interpret the small diphoton excess seen by CMS at its central value, when m_s■ 95 GeV,η■0.6 and | sinθ_S|■0.(iv) The large-diphoton scenario in general predicts a negative correlation between the Higgs couplings |C_(hγγ)/SMI and |C_(hgg)/SM|, while the small-diphoton scenario predicts that both couplings are smaller than 1,or |C_(hγγ)/SM|■0.9■|C_(hgg)/SM|.

Fermions tunneling from the Horowitz-Strominger Dilaton black hole

Based on the work of Kerner and Mann, fermions tunneling from the Horowitz-Strominger Dilaton black hole on the membrane is studied. Owing to the coupling among electromagnetic field, matter field and gravity field, the Dirac equation of charged particles is introduced, and according to that, the expected emission temperature is obtained. After the self-gravitational interaction is considered, it is found that the tunneling rate of fermions also satisfies the underlying Unitary theory as the case of scalar particles.

The entropy of Garfinkle-Horne dilaton black hole due to arbitrary spin fields

Using the membrane model which is based on brick wall model, we calculated the free energy and entropy of Garfinkle-Horne dilatonic black hole due to arbitrary spin fields. The result shows that the entropy of scalar field and the entropy of Fermionic field have similar formulas. There is only a coefficient between them.

Generalized Jackiw-Teitelboim gravity in presence of Block brane-like models

We investigate generalized Jackiw-Teitelboim gravity,coupling the dilaton field with two scalar matter fields.We obtain the equations of motion for the fields and investigate a linear perturbation of the solutions in general.We study two specific situations that allow for analytic solutions with topological behavior and check how the dilaton field,the warp factor and the Ricci scalar behave.In particular,we show how the parameters can be used to modify the structure of the solutions.Moreover,the perturbations are,in general,described by intricate coupled differential equations,but in some specific cases,we can construct the corresponding zero modes analytically.