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稳态轴对称爱因斯坦—麦克斯韦伸缩子黑洞时空中标量场的衰减

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稳态轴对称爱因斯坦—麦克斯韦伸缩子黑洞时空中标量场的衰减

作者：潘启沅湖南师范大学

学位级别：硕士

弦理论是目前唯一能够量子化引力并将引力与电磁、弱和强相互作用统一起来的自治理论。这一理论具有解释宇宙起源与运行以及现代物理中很多难题的潜力。由弦理论得到的伸缩子黑洞,其时空有着与通常广义相对论中的时空不一样的性质,其原... 详细信息

弦理论是目前唯一能够量子化引力并将引力与电磁、弱和强相互作用统一起来的自治理论。这一理论具有解释宇宙起源与运行以及现代物理中很多难题的潜力。由弦理论得到的伸缩子黑洞,其时空有着与通常广义相对论中的时空不一样的性质,其原因在于伸缩子参数的存在。因此,多年来人们对伸缩子时空的各种研究极为关注。但是,在含伸缩子时空中扰动场的演化研究方面,由于问题的复杂性,人们目前只讨论了静态球对称情况。由于稳态时空具有更普遍的性质,所以研究低能弦理论稳态轴对称解的伸缩子时空中标量场的衰减行为是非常有意义的。本文中我们将研究在该时空背景下标量场的拖尾以及似正模等问题。利用引入了频谱分解技术的格林函数,我们对稳态轴对称爱因斯坦—麦克斯韦伸缩子黑洞时空中无质量和有质量标量场的晚期拖尾进行了解析的研究。结果表明:无质量扰动场的晚期渐近行为将由负幂律拖尾t-(2l+3)主导,有质量标量扰动场的中晚期衰减行为由振荡负幂律拖尾t-(l+3/2))sin(μt)主导,而极晚期则由一种衰减更缓慢的振荡负幂律拖尾t-(5/6))sin(μt)主导。我们认为,极晚期的振荡负幂律拖尾t-(5/6))sin(μt)是任意四维渐近平直旋转时空中有质量标量扰动场晚期衰减的普遍形式。另一方面,我们利用Leaver最先提出的连续分数法对这一伸缩子时空中无质量标量似正模进行了数值的计算。我们获得了缓慢衰减的似正频率即基频,并且对它们的行为进行研究。结果表明:(1)这些标量似正模受制于伸缩子参数D、旋转参数a、多极矩l和磁量子数m;(2)在a、l和m相同的情况下,似正模基频的实部ωR随着D的减小始终是增大的,但是虚部ωI总会有一个先减小后增大的过程;(3)在D和l相同的情况下,当m≥0时,似正模基频的实部ωR和虚部ωI一般都会随着a的增加而增大,而当m<0时,似正模基频的实部ωR会随着a的增加而减小,虚部ωI则一般出现一个先减小后增大的过程;(4)在D和a相同的情况下,似正模基频的实部ωR只会随着l的增加而增大,除个别情况外,虚部ωI一般也会增大;(5)在D和l相同的情况下,当a=0即对于静态黑洞,m对似正模不存在任何影响,而当a≠0即对于

关键词：晚期拖尾稳态轴对称爱因斯坦-麦克斯韦伸缩子黑洞引入频谱分解技术的格林函数负幂律衰减拖尾似正模连续分数法

Resonant frequencies of massless scalar field in rotating black-brane spacetime

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Chinese Physics B 2008年第6期17卷 1985-1989页

作者：荆继良潘启沅 Key Laboratory of Low Dimensional Quantum Structures and Quantum Control Ministry of Education Institute of Physics Hunan Normal University

This paper investigates the resonant frequencies of the massless scalar field in the near extremal Kerr-like black-brane spacetime. It is shown that the different angular quantum number will present different resonant frequencies. It is also shown that the real part of the resonant frequencies increases as the compact dimensions parameter μi increases, but the magnitude of the imaginary part decreases as μi increases.

关键词： resonant frequency black brane scalar field

Asymptotic Tails of Massive Scalar Fields in a Stationary Axisymmetric EMDA Black Hole Geometry

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Chinese Physics Letters 2004年第10期21卷 1873-1876页

作者：潘启沅荆继良 InstituteofPhysics HunanNormalUniversityChangsha410081

The late-time tail behaviour of massive scalar fields is studied analytically in a stationary axisymmetric Einstein–Maxwell Dilaton–Axion (EMDA) black hole geometry. It is shown that the asymptotic behaviour of massive perturbations is dominated by the oscillatory inverse power-law decaying tail t−(l+3/2)sin (μt) at the intermediate late times, and by the asymptotic tail t−5/6sin (μt) at asymptotically late times, with μ being field mass. Our result seems to suggest that the intermediate tails t−(l+3/2)sin (μt) and the asymptotically tails t−5/6sin (μt) may be a quite general feature for evolution of massive scalar fields in any four-dimensional asymptotically flat rotating black hole backgrounds.

关键词： Gravitation

Quasinormal Modes of Phantom Scalar Perturbation in Background of Reissner-Nordstrom Black Hole

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Communications in Theoretical Physics 2011年第2期55卷 221-226页

作者：潘启沅苏汝铿 Department of Physics Fudan University Institute of Physics and Department of Physics Hunan Normal University

We have investigated the quasinormal modes (QNMs) of phantom scalar perturbation in a Reissner-Nordstrm (RN) *** find that the dependence of QNMs on the mass of the field for the phantom perturbation is totally different from that of usual massive ***,we obtain the same critical value of the overtone number for an angular quantum number from which the mass will begin to have a reverse effect on the real part of QNM frequencies and the perturbation-independent relation between the QNMs and the second order thermodynamic phase transition.

关键词：扰动标量正规模幻影黑洞网管系统角量子数二阶摄动

Holographic p-Wave Superconductors in Quintessence AdS Black Hole Spacetime

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Communications in Theoretical Physics 2013年第10期60卷 471-478页

作者：陈松柏潘启沅 Institute of Physics and Department of Physics Hunan Normal University Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education Hunan Normal University

We construct a holographic p-wave superconductor model in the background of quintessence AdS black hole with an SU(2)Yang–Mills gauge field and then probe the efects of quintessence on the holographic p-wave *** investigate the relation between the critical temperature and the state parameter of quintessence,and present the numerical results for electric *** is shown that the condensation of the vector field becomes harder as the absolute value of the state parameter *** the scalar condensate in the s-wave model,the condensation of the vector field in p-wave model can occur in the total value range of the state parameter wq of *** results could help us know more about holographic superconductor and dark energy.

关键词：超导体全息黑洞广告时空 P波背景模型状态参数

安徽省土壤阳离子交换量传递函数构建与精度评价

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土壤通报 2024年第2期55卷 374-382页

作者：潘启凤曾荣南京信息工程大学地理科学学院江苏南京210044

[目的]由于化学测定方法费时费力,很多历史土壤资料缺少阳离子交换量(CEC)信息。本研究旨在基于易获取的变量建立安徽省土壤CEC的预测模型。[方法]利用覆盖安徽全省区域的711个土样的有机质含量、颗粒组成和土壤pH的信息,采用逐步多元... 详细信息

[目的]由于化学测定方法费时费力,很多历史土壤资料缺少阳离子交换量(CEC)信息。本研究旨在基于易获取的变量建立安徽省土壤CEC的预测模型。[方法]利用覆盖安徽全省区域的711个土样的有机质含量、颗粒组成和土壤pH的信息,采用逐步多元线性回归方法建立CEC预测模型;并按土壤层次、土壤类型、母质、土地利用方式、质地和石灰性六种分组方式检验了其对模型预测精度的影响。[结果](1)利用全省未分组数据建立的预测模型精度较低,调整R^(2)仅为0.33;(2)按土壤类型、土地利用方式和石灰性进行分组,整体上可提高模型的预测精度,调整R2提升至0.44~0.93;但按土壤层次、母质和质地进行分组,模型精度未得到明显改善甚至有所下降;(3)预测安徽省土壤CEC的参数重要性依次为土壤黏粒含量、土壤有机质含量和土壤pH。[结论]基于未分组数据集上建立的安徽省土壤CEC模型精度很低,依据土壤类型、土地利用方式和石灰性进行分组可提高CEC的预测精度,对CEC预测最重要的变量是土壤黏粒含量,其次是土壤有机质含量和土壤pH。

关键词：土壤阳离子交换量传递函数有机质黏粒 pH

Holographic Superconductor Models with RF^(2) Corrections

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Chinese Physics Letters 2013年第12期30卷 17-20页

作者：赵紫旭潘启沅荆继良 Institute of Physics and Department of Physics Hunan Normal UniversityChangsha 410081 Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Hunan Normal UniversityChangsha 410081

We investigate the effect of the RF^(2) correction on the holographic superconductor model in the background of AdS black hole,where R is the Ricci scalar of spacetime and F^(2)=FμνFμνis the Maxwell field *** observe that,similar to the effect caused by the Weyl correction,the higher RF^(2) correction term can make it easier for the scalar operator to condense and result in the larger deviation from the expected relation in the gap ***,we find that the condensation gap becomes larger as the RF^(2) correction term increases,which is in strong contrast to the influences of the Weyl correction and Gauss–Bonnet correction.

关键词： strength correction scalar

Quasinormal modes of a stationary axisymmetric EMDA black hole

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Chinese Physics B 2006年第1期15卷 77-82页

作者：潘启沅荆继良 Institute of Physlcs Hunan Normal University Changsha 410081 China

The massless scalar quasinormal modes (QNMs) of a stationary axisymmetric Einstein-Maxwell dilaton-axion (EMDA) black hole are calculated numerically using the continued fraction method first proposed by Leaver. The fundamental quasinormal frequencies (slowly damped QNMs) are obtained and the peculiar behaviours of them are studied. It is shown that these frequencies depend on the dilaton parameter D, the rotational parameter a, the multiple moment l and the azimuthal number m, and have the same values with other authors at the Schwarzschild and Kerr limit.

关键词：准常态模式固定轴对称EMDA黑洞多重力矩方位角数

Late-time tails in a stationary axisymmetric EMDA black hole geometry

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Chinese Physics B 2005年第2期14卷 268-273页

作者：潘启沅荆继良 InstituteofPhysics HunanNormalUniversityChangsha410081China

The late-time tails of massless and self-interacting (SI) (massive) scalar fields are investigated analytically in a stationary axisymmetric Einstein-Maxwell dilaton-axion (EMDA) black hole geometry. It is shown that the asymptotic behaviour of massless perturbations is dominated by an inverse power-law decaying tail and the intermediate asymptotic behaviour of SI (massive) perturbations is dominated by an oscillatory one.

关键词： late-time tail stationary axisymmetric EMDA black hole inverse power-law decayingtail