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The microstructure and Ruppeiner geometry of charged anti-de Sitter black holes in Gauss-Bonnet gravity:from the critical point to the triple point

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Communications in Theoretical Physics 2022年第9期74卷 131-144页

作者： shao-wen wei Yu-Xiao Liu Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu ProvinceSchool of Physical Science and TechnologyLanzhou UniversityLanzhou 730000China Institute of Theoretical Physics&Research Center of Gravitation Lanzhou UniversityLanzhou 730000China Academy of Plateau Science and Sustainability Qinghai Normal UniversityXining 810016China

Ruppeiner geometry has been successfully applied in the study of the black hole microstructure by combining with the small-large black hole phase transition,and the potential interactions among the molecular-like constituent degrees of freedom are *** this paper,we will extend the study to the triple point,where three black hole phases coexist acting as a typical feature of black hole systems quite different from the small-large black hole phase *** the six-dimensional charged Gauss-Bonnet anti-de Sitter black hole,we thoroughly investigate the swallow tail behaviors of the Gibbs free energy and the equal area *** obtaining the black hole triple point in a complete parameter space,we exhibit its phase structures both in the pressure-temperature and temperature-horizon radius *** different from the liquid-vapor phase transition,a double peak behavior is present in the temperature-horizon radius phase *** we construct the Ruppeiner geometry and calculate the corresponding normalized curvature *** the triple point,we observe multiple negatively divergent *** curvature scalar is observed for the small black hole with high temperature,which indicates that the repulsive interaction dominates among the ***,we consider the variation of the curvature scalar along the coexisting intermediate and large black hole *** with the observation for different fluids,the result suggests that this black hole system behaves more like the argon or *** study provides a first and preliminary step towards understanding black hole microstructure near the triple point,as well as uncovering the particular properties of the Gauss-Bonnet gravity.

关键词： black hole thermodynamics phase transition black hole microstructure Gauss-Bonnet gravity

Quantization of black hole entropy from unstable circular null geodesics

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Science China(Physics,Mechanics & Astronomy) 2016年第4期59卷 29-36页

作者： shao-wen wei Yu-Xiao Liu Chun-E Fu Institute of Theoretical Physics Lanzhou University School of Science Xi'an Jiaotong University

The quasinormal mode frequencies can be understood from the massless particles trapped at the unstable circular null geodesics and slowly leaking out to infinity. Based on this viewpoint, in this paper, we semiclassically construct the entropy spectrum of the static and stationary black holes from the null geodesics. The result shows that the spacing of the entropy spectrum only depends on the property of the black hole in the eikonal limit. Moreover, for a black hole far from the extremal case, the spacing is found to be smaller than 2π for any dimension, which is very different from the result of the previous work by using the usual quasinormal mode frequencies.

关键词： black hole entropy spectrum null geodesics quantization

Implementing Black Hole as Efficient Power Plant

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Communications in Theoretical Physics 2019年第6期71卷 711-717页

作者： shao-wen wei Yu-Xiao Liu Institute of Theoretical Physics & Research Center of Gravitation Lanzhou University

Treating the black hole molecules as working substance and considering its phase structure, we study the black hole heat engine by a charged anti-de Sitter black hole. In the reduced temperature-entropy chart, it is found that the work, heat, and efficiency of the engine are free of the black hole charge. Applying the Rankine cycle with or without a back pressure mechanism to the black hole heat engine, the compact formula for the efficiency is *** the heat, work and efficiency are worked out. The result shows that the black hole engine working along the Rankine cycle with a back pressure mechanism has a higher efficiency. This provides a novel and efficient mechanism to produce the useful mechanical work, and such black hole heat engine may act as a possible energy source for the high energy astrophysical phenomena near the black hole.

关键词： black hole heat engine phase transition

Null geodesics,quasinormal modes,and thermodynamic phase transition for charged black holes in asymptotically flat and dS spacetimes

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Chinese Physics C 2020年第11期44卷 220-231页

作者： shao-wen wei Yu-Xiao Liu Institute of Theoretical Physics&Research Center of Gravitation Lanzhou UniversityLanzhou 730000China Department of Physics and Astronomy University of WaterlooWaterlooOntarioN2L 3G1Canada

A numerical study has indicated that there exists a relation between the quasinormal modes and the Davies point for a black *** this paper,we analytically study this relation for charged Reissner-Nordstrom black holes in asymptotically flat and de Sitter(dS)spacetimes in the eikonal limit,under which the quasinormal modes can be obtained from the null geodesics using the angular velocity Ω and the Lyapunov exponentλof the photon *** in asymptotically flat and dS spacetimes,we observe spiral-like shapes in the complex quasinormal mode ***,the starting point of the shapes does not coincide with the Davies ***,we find a new relation in which the Davies point exactly meets the maximum temperature T in the T-Ω and T-λ *** a higher-dimensional asymptotically flat spacetime,although there is no spiral-like shape,such a relation still ***,we provide a new relation between black hole thermodynamics and dynamics in the eikonal *** this relation,we can test the thermodynamic property of a black hole using the quasinormal modes.

关键词： black holes phase transition photon sphere

Observing dynamic oscillatory behavior of triple points among black hole thermodynamic phase transitions

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Science China(Physics,Mechanics & Astronomy) 2021年第7期64卷 66-71页

作者： shao-wen wei Yong-Qiang Wang Yu-Xiao Liu Robert B.Mann Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu ProvinceSchool of Physical Science and TechnologyLanzhou UniversityLanzhou730000China Institute of Theoretical Physics&Research Center of Gravitation Lanzhou UniversityLanzhou730000China Department of Physics and Astronomy University of WaterlooWaterlooN2L 3G1Canada

Understanding the dynamic process of black hole thermodynamic phase transitions at a triple point is a huge challenge. In this paper, we conduct the first investigation of dynamic phase behavior at a black hole triple point. By numerically solving the Smoluchowski equation near the triple point for a six-dimensional charged Gauss-Bonnet anti-de Sitter black hole, we report that initial small, intermediate, or large black holes can transit to the other two coexistent phases at the triple point, indicating that thermodynamic phase transitions can indeed occur dynamically. More significantly, we observe characteristic weak and strong oscillatory behavior in this dynamic process, which can be understood from an investigation of the rate of first passage from one phase to another. Our results further an understanding of the dynamic process of black hole thermodynamic phase transitions.

关键词： classical black hole thermodynamics phase transition Smoluchowski equation first passage time

Thermodynamic Geometry of Charged AdS Black Hole Surrounded by Quintessence

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Communications in Theoretical Physics 2018年第2期69卷 173-178页

作者： shao-wen wei Qing-Tao Man Hao Yu Institute of Theoretical Physics Lanzhou University Lanzhou 730000 China

In this paper, we study the thermodynamic geometry for the charged Ad S black hole surrounded by quintessence. Three different kinds of the geometries are constructed, and the corresponding curvatures are obtained. It is found that there are different divergence behaviors of these curvatures, which is general thought to closely link to the phase transition of the black hole.

关键词： phase transition black hole thermodynamic geometry

QED effects on phase transition and Ruppeiner geometry of Euler-Heisenberg-AdS black holes

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Chinese Physics C 2022年第11期46卷 291-307页

作者： Xu Ye Zi-Qing Chen Ming-Da Li shao-wen wei Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu ProvinceSchool of Physical Science and TechnologyLanzhou UniversityLanzhou 730000China Institute of Theoretical Physics&Research Center of Gravitation Lanzhou UniversityLanzhou 730000China Academy of Plateau Science and Sustainability Qinghai Normal UniversityXining 810016China

Considering the quantum electrodynamics(QED)effect,we study the phase transition and Ruppeiner geometry of Euler-Heisenberg anti-de Sitter black holes in the extended phase *** negative and small positive QED parameters,we observe a small/large black hole phase transition and reentrant phase transition,respectively,whereas a large positive value of the QED parameter ruins the phase *** diagrams for each case are explicitly ***,we construct the Ruppeiner geometry in thermodynamic parameter *** features of the corresponding scalar curvature are shown for both the small/large black hole phase transition and reentrant phase transition *** particular interest is the additional region of positive scalar curvature,indicating a dominant repulsive interaction among black hole microstructures,for the black hole with a small positive QED ***,universal critical phenomena are observed for the scalar curvature of Ruppeiner *** results indicate that the QED parameter has a crucial influence on the black hole phase transition and microstructure.

关键词： black holes thermodynamics phase transition Ruppeiner geometry

New insights into thermodynamics and microstructure of AdS black holes

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Science Bulletin 2020年第4期65卷 259-261页

作者： shao-wen wei Yu-Xiao Liu Institute of Theoretical Physics&Research Center of Gravitation Lanzhou UniversityLanzhou 730000China

Black hole, a strange object of extreme gravity, is gradually believed to be a thermodynamic system after 1972. The area and the surface gravity of black hole event horizon were found to be closely related with the entropy and Hawking temperature. Then four thermodynamic laws were established [1]. Black hole phase transition as a characteristic nature and microstructure indicator has attracted a lot of attention.

关键词： AdS 黑洞热力学微观结构

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体外培养的神经元网络可塑性

生物化学与生物物理进展 2024年第5期51卷 1000-1009页

作者：邵琪孟维伟李晓红邵文威天津大学医学工程与转化医学研究院天津300072

神经元网络是大脑执行高级认知行为的结构基础,研究证明学习记忆及神经退行性疾病与神经元网络可塑性密切相关。因此,揭示调控和改变神经元网络可塑性的机制对理解神经系统信息交互以及疾病治疗具有重大意义。目前,基于微电极阵列(micro... 详细信息

神经元网络是大脑执行高级认知行为的结构基础,研究证明学习记忆及神经退行性疾病与神经元网络可塑性密切相关。因此,揭示调控和改变神经元网络可塑性的机制对理解神经系统信息交互以及疾病治疗具有重大意义。目前,基于微电极阵列(microelectrode array,MEA)培养的神经元网络是体外探究学习和记忆机制的理想模型,同时针对该模型的研究为预防和治疗神经退行性疾病提供了独特的视角。本文综述了基于MEA采集体外培养神经元网络的放电信号来构建功能网络的相关研究,分别从二维神经元网络和三维脑类器官发育,以及开环和闭环电刺激对神经元网络可塑性影响的角度,总结了体外培养神经元网络可塑性的相关研究,最后对该方向的应用前景进行了展望。

关键词：微电极阵列可塑性功能网络发育电刺激调控