检索结果-南通市图书馆

Effects of dark matter on shadows and rings of Brane-World black holes illuminated by various accretions

Science China(Physics,Mechanics & Astronomy) 2022年第9期65卷 27-43页

作者： Xiao-Xiong Zeng ke-jian he Guo-Ping Li State key Laboratory of Mountain Bridge and Tunnel Engineering Chongqing Jiaotong UniversityChongqing 400074China Department of Mechanics Chongqing Jiaotong UniversityChongqing 400074China College of Physics Chongqing UniversityChongqing 401331China Physics and Space College China West Normal UniversityNanchong 637000China

In this study, by taking the accretions into account, the observed shadows and rings cast by the Brane-World black hole were numerically investigated when the observer was located at the cosmological horizon. The results showed that the radius rpof the photon sphere increased with the cosmological parameter α and dark matter parameter β, while the impact parameter bpdecreased with α and increased with β. For thin disk accretion, the total observed intensity is mainly composed of direct ***, the lensing ring and photon ring have only small and negligible contributions, respectively. We also found that shadows and rings exhibit different and exciting features when the disk is located at different positions. For static and infalling spherical accretions, it is evident that the size of shadows is always the same for both accretions. This implies that shadows are only related to space-time geometry in this case. The luminosity of the shadow and photon sphere is closely associated with the Doppler effect and the emissivity per unit volume j(νe). In addition, the influence of dark matter and cosmological constant on the observed intensity of shadows and rings is carefully emphasized throughout this paper. Finally, we obtained the burring images of shadows and rings using the nominal resolution of the event horizon telescope. We also studied the upper limits of the X-clod dark matter parameter β using the data of the shadow of M87.

关键词： dark matter the accretion black hole shadow lensing and photon rings

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Shadows and observation intensity of black holes in the Randall–Sundrum brane world model

引用

Chinese Physics C 2022年第7期46卷 212-219页

作者： ke-jian he Xiao Zhang Xin Li Department of Physics and Chongqing key Laboratory for Strongly Coupled Physics Chongqing University Chongqing 401331China Hongshen Honors School Chongqing UniversityChongqing 401331China

The shadow and observation intensity of a black hole surrounded by a thin spherical accretion in the Randall–Sundrum brane world model are *** bulk metric depends on the tidal charge parameter,q,and deformation parameter,*** reduces to the metric that possesses similar form with the Reissner–Nordström metric if C=*** is shown that the radius of the photon sphere of this black hole depends only on the tidal charge *** radius of the photon sphere decreases with higher *** observation intensity is mainly influenced by the tidal charge parameter,q,and the deformation parameter,C,is of secondary *** the optical observation,the black holes appear brighter with higher q or lower C.

关键词： shadows observation intensity Randall-Sundrum brane

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of torsion charge on optical appearance and additional photon rings of an asymmetric thin-shell wormhole

引用

Chinese Physics C 2024年第11期48卷 138-148页

作者： Qi-Qin Jing ke-jian he Zhi Luo Sichuan Province Beichuan High School Beichuan 622750China Department of Mechanics Chongqing Jiaotong UniversityChongqing 400074China Department of Physics Chongqing UniversityChongqing 401331China

In this paper,we study the optical properties of asymmetric thin-shell wormholes(ATWs)under torsion *** the cut-and-paste method developed by Visser,we construct these wormholes and determine their key physical properties,such as the radius of the photon sphere and critical impact parameters,under different torsion ***,we investigate the effective potential and behavior of photon motion within the wormhole spacetime,identifying a relationship between photon trajectories and impact *** study focuses on scenarios where thin accretion disks act as the primary light *** reveals that the optical features of ATWs under torsion charge significantly differ from those of black holes(BHs).Notably,an increase in torsion charge leads to a reduction in the sizes of both extra photon rings and lensing bands,which serve as important markers for distinguishing and characterizing ATW spacetimes from those of BHs.

关键词： asymmetric thin-shell wormhole torsion charge additional photon ring

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Shadows and observational appearance of a new family of Ayón-Beato-García black holes

引用

Communications in Theoretical Physics 2022年第12期74卷 87-96页

作者： Ping-Hui Mou Yun-Xian Chen ke-jian he Guo-Ping Li School of Physics and Astronomy China West Normal UniversityNanchong 637000China Department of Physics and Chongqing key Laboratory for Strongly Coupled Physics Chongqing UniversityChongqing 401331China

In this paper,we study the shadows and observational appearance of the Ayón-Beato-García(ABG)black hole,which is surrounded by a thin disk *** a four-dimensional ABG black hole,as the charge q increases,the event horizon r+,radius rp and impact parameter bp of the photon sphere decrease,while the maximum value of effective potential Veff ***,as the termγassociated with nonlinear electrodynamics increases,the related physical quantities r+,rp and bp increase,but the maximum value of Veff *** the light ray reaches the vicinity of the ABG black hole,one can observe the trajectories of the light rays appearing as three types,i.e.,direct emission,lens ring and photon ***,the shadows and the observational appearance of the ABG black hole are *** results show that the charge q and the termγhave a great influence on the shape and intensity of the black hole *** the relevant state parameters change or the emission model changes,it can be argued that it is the direct emission that plays a decisive role in the total observed intensity of the ABG black hole,while the contribution of the lens ring to the total observed intensity is small and the photon ring makes almost no contribution.

关键词： black hole shadow thin disk accretion rings

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Holographic images of an AdS black hole within the framework of f(R) gravity theory

引用

Frontiers of physics 2024年第5期19卷 35-47页

作者： Guo-Ping Li ke-jian he Xin-Yun Hu Qing-Quan jiang School of Physics and Astronomy China West Normal UniversityNanchong 637000China College Of Physics Chongqing UniversityChongqing 401331China College of Economic and Management Chongqing Jiaotong UniversityChongqing 400074China

Based on the AdS/CFT correspondence,this study employs an oscillating Gaussian source to numerically study the holographic images of an AdS black hole under f(R)gravity using wave *** to the diffraction of scalar wave,it turns out that one can clearly observed the interference patten of the absolute amplitude of response function on the AdS ***,it is observed that its peak increases with the f(R)parameterαbut decreases with the global monopoleη,frequencyω,and horizon r_(h).More importantly,the results reveal that the holographic Einstein ring is a series of concentric striped patterns for an observer at the North Pole and that their center is analogous to a Poisson-Arago *** ring can evolve into a luminosity-deformed ring or two light spots when the observer is at a different *** to geometrical optics,it is true that the size of the brightest holographic ring is approximately equal to that of the photon sphere,and the two light spots correspond to clockwise and anticlockwise light *** addition,holographic images for different values of black holes and optical system parameters were obtained,and different features ***,we conclude that the holographic rings of the AdS black hole in modified gravities are more suitable and helpful for testing the existence of a gravity dual for a given material.

关键词： AdS black hole holographic images AdS/CFT correspondence

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Weak cosmic censorship conjecture and thermodynamics in quintessence Ad S black hole under charged particle absorption

引用

Chinese Physics C 2019年第12期43卷 169-179页

作者： ke-jian he Xin-Yun Hu Xiao-Xiong Zeng Physics and Space College China West Normal UniversityNanchong 637000China College of Economic and Management Chongqing Jiaotong UniversityChongqing 400074China State key Laboratory of Mountain Bridge and Tunnel Engineering Chongqing Jiaotong UniversityChongqing 400074China Department of Mechanics Chongqing Jiaotong UniversityChongqing 400074China

Considering the cosmological constant as the pressure,this study addresses the laws of thermodynamics and weak cosmic censorship conjecture in the Reissner-Nordstrom-AdS black hole surrounded by quintessence dark energy under charged Particle *** first law of thermodynamics i5 found to be valid as a Particle is absorbed by the black *** second law,however,is violated for the extremal and near-extremal black holes,because the entropy of these black hole ***,we find that the extremal black hole does not change its configuration in the extended phase space,implying that the weak cosmic censorship conjecture is ***,the near-extremal black hole can be overcharged beyond the extremal condition under charged particle ***,the cosmic censorship conjecture could be violated for the near-extremal black hole in the extended phase *** comparison,we also discuss the first law,second law,and the weak cosmic censorship conjecture in normal phase space,and find that all of them are valid in this case.

关键词： thermodynamics weak cosmic censorship conjecture quintessence AdS black hole

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Thermodynamics and weak cosmic censorship conjecture of an AdS black hole with a monopole in the extended phase space

引用

Chinese Physics C 2020年第5期44卷 133-139页

作者： Xin-Yun Hu ke-jian he Xiao-Xiong Zeng jian-Pin Wu College of Economic and Management Chongqing Jiaotong UniversityChongqing 400074China Physics and Space College China West Normal UniversityNanchong 637000China Department of Mechanics Chongqing Jiaotong UniversityChongqing 400074China Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China

The first law of black hole thermodynamics has been shown to be valid in the extended phase ***,the second law and the weak cosmic censorship conjecture have not been investigated *** investigate the laws of thermodynamics and the weak cosmic censorship conjecture of an AdS black hole with a global monopole in the extended phase space in the case of charged particle *** is shown that the first law of thermodynamics is valid,while the second law is violated for the extremal and near-extremal black ***,we find that the weak cosmic censorship conjecture is valid only for the extremal black hole,and that it can be violated for the near-extremal black holes,which is different from the previous results.

关键词： weak cosmic censorship conjecture thermodynamics global monopole black holes

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Lorentz violation, quantum tunneling, and information conservation

引用

Chinese Physics C 2021年第1期45卷 427-437页

作者： Guo-Ping Li ke-jian he Bing-Bing Chen Physics and Space College China West Normal UniversityNanchong 637000China Department of Physics Si Chuan MinZu CollegeKangding 626001China

In this paper, by introducing the Lorentz-invariance-violation(LIV) class of dispersion relations(DR)suppressed by the second power(E/EQG)2, we investigated the effect of the LIV on the Hawking radiation of a charged Dirac particle based on tunneling from a Reissner-Nordstrom(RN) black hole. It was determined that the LIV speeds up black hole evaporation. As a result, the induced Hawking temperature was very sensitive to changes in the energy of the radiation particle. However, at the same energy level, it was insensitive to changes in the charge of the radiation particle. This is phenomenological evidence in support of the LIV-DR as a candidate for describing the effect of quantum gravity. Moreover, when the effect of the LIV was included, we discovered that the statistical correlations with the Planck-scale corrections between successive emissions could leak out information via *** also determined that black hole radiation via tunneling is an entropy conservation process, and no information loss occurred during radiation, where the interpretation of the entropy of a black hole is addressed. Finally, we concluded that black hole evaporation is still a unitary process in the context of quantum gravity.

关键词： Lorentz violation quantum tunneling information conservation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Thermodynamics and weak cosmic censorship conjecture of charged AdS black hole in the Rastall gravity with pressure

引用

Chinese Physics B 2020年第5期29卷 142-148页

作者： Xin-Yun Hu ke-jian he Zhong-Hua Li Guo-Ping Li College of Economic and Management Chongqing Jiaotong UniversityChongqing 400074China Physics and Space College China West Normal UniversityNanchong 637000China

Treating the cosmological constant as a dynamical variable,we investigate the thermodynamics and weak cosmic censorship conjecture(WCCC)of a charged AdS black hole(BH)in the Rastall *** determine the energy momentum relation of charged fermion at the horizon of the BH using the Dirac *** on this relation,it is shown that the first law of thermodynamics still holds as a fermion is absorbed by the ***,the entropy of both the extremal and near-extremal BH decreases in the irreversible process,which means that the second law of thermodynamics is ***,we verify the validity of the WCCC by the minimum values of the metric function h(r)at its final *** the extremal charged AdS BH in the Rastall gravity,we find that the WCCC is always valid since the BH is *** for the case of near-extremal BH,we find that the WCCC could be violable in the extended phase space(EPS),depending on the value of the parameters of the BH and their variations.

关键词： Rastall gravity extended phase space black hole thermodynamics weak cosmic censorship conjecture

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Shadow images and observed luminosity of the Bardeen black hole surrounded by different accretions

引用

Chinese Physics C 2022年第8期46卷 273-286页

作者： ke-jian he Sen Guo Shuang-Cheng Tan Guo-Ping Li Department of Physics and Chongqing key Laboratory for Strongly Coupled Physics Chongqing UniversityChongqing 401331China Guangxi key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Physics and Space College China West Normal UniversityNanchong 637000China

In this paper,by exploring photon motion in the region near a Bardeen black hole,we studied the shadow and observed properties of the black hole surrounded by various accretion *** analyzed the changes in shadow imaging and observed luminosity when the relevant physical parameters are *** the different spherical accretion backgrounds,we find that the radius of shadow and the position of the photon sphere do not change,but the observed intensity of shadow in the infalling accretion model is significantly lower than that in the static *** also studied the contribution of the photon rings,lensing rings and direct emission to the total observed flux when the black hole is surrounded by an optically thin disk *** the different forms of the emission modes,the results show that the observed brightness is mainly determined by direct emission,while the lensing rings will provide a small part of the observed flux,and the flux provided by the photon ring is *** comparing our results with the Schwarzschild spacetime,we find that the existence or change of relevant status parameters will greatly affect the shape and observed intensity of the black hole *** results support the theory that the change of state parameter will affect the spacetime structure,thus affecting the observed features of black hole shadows.

关键词： shadow observed luminosity Bardeen black hole

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：