arXiv - PHYS - General Relativity and Quantum Cosmology最新文献

Spontaneous scalarization of Bardeen black holes 巴丁黑洞的自发标量化

arXiv - PHYS - General Relativity and Quantum Cosmology Pub Date : 2024-09-18 DOI: arxiv-2409.11669

Lina Zhang, Qiyuan Pan, Yun Soo Myung, De-Cheng Zou

引用次数: 0

Holographic Einstein Rings of AdS Black Holes in Horndeski Theory 霍恩德斯基理论中 AdS 黑洞的全息爱因斯坦环

arXiv - PHYS - General Relativity and Quantum Cosmology Pub Date : 2024-09-18 DOI: arxiv-2409.11885

Zhi Luo, Ke-Jian He, Jin Li

{"title":"Holographic Einstein Rings of AdS Black Holes in Horndeski Theory","authors":"Zhi Luo, Ke-Jian He, Jin Li","doi":"arxiv-2409.11885","DOIUrl":"https://doi.org/arxiv-2409.11885","url":null,"abstract":"By utilizing the AdS/CFT correspondence and wave optics techniques, we\u0000conducted an extensive study of the imaging properties of holographic Einstein\u0000rings in the context of Anti-de Sitter (AdS) black holes (BHs) in Horndeski\u0000theory. Our results indicate that the optical characteristics of these\u0000holographic Einstein rings are significantly influenced by the observer's\u0000position, the physical parameters of the BH, the nature of the wave source, and\u0000the configuration of the optical system. Specifically, when the observer is\u0000positioned at the north pole of the AdS boundary, the holographic image\u0000prominently displays a ring structure aligning with the BH's photon sphere. We\u0000thoroughly analyzed how various physical parameters -- including the\u0000observation position, event horizon radius, temperature, and the parameter\u0000$gamma$ in Horndeski theory -- affect the holographic Einstein rings. These\u0000parameters play a crucial role in determining the rings' radius and brightness,\u0000with variations potentially causing the ring structures to deform or even\u0000transform into bright spots. Furthermore, our comparative analysis between wave\u0000optics and geometric optics reveals a strong agreement in predicting the\u0000positions and brightnesses of both the photon ring and the Einstein ring. This\u0000research offers new insights into the spacetime geometry of BHs in Horndeski\u0000theory and proposes a promising framework for exploring the gravitational duals\u0000of strongly coupled systems.","PeriodicalId":501041,"journal":{"name":"arXiv - PHYS - General Relativity and Quantum Cosmology","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142250718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Matter Geometry Coupling and Casimir Wormhole Geometry 物质几何耦合与卡西米尔虫洞几何

arXiv - PHYS - General Relativity and Quantum Cosmology Pub Date : 2024-09-18 DOI: arxiv-2409.12160

A. S. Agrawal, Sankarsan Tarai, B. Mishra, S. K. Tripathy

{"title":"Matter Geometry Coupling and Casimir Wormhole Geometry","authors":"A. S. Agrawal, Sankarsan Tarai, B. Mishra, S. K. Tripathy","doi":"arxiv-2409.12160","DOIUrl":"https://doi.org/arxiv-2409.12160","url":null,"abstract":"In this study, we investigate traversable wormhole solutions within the setup\u0000of $f(R,mathcal{L}_{m})$ gravity, a modified theory of gravity where the\u0000gravitational action relies upon the matter Lagrangian $mathcal{L}_{m}$ and\u0000the Ricci scalar $R$. In General Relativity (GR), stability issues in\u0000traversable wormholes necessitate the existence of exotic matter that violates\u0000the null energy condition (NEC). In contrast, we explore wormhole solutions\u0000that align with the criteria for Casimir wormholes, which do not necessarily\u0000require NEC violation. Our analysis demonstrates that in the context of\u0000$f(R,mathcal{L}_{m})$ gravity, exotic matter can sustain these wormholes. We\u0000further examine the traversability conditions of the wormhole, considering both\u0000scenarios with and without the Generalized Uncertainty Principle (GUP)\u0000correction. Additionally, the stability of the wormhole is assessed based on\u0000equilibrium conditions. Our findings suggest that $f(R,mathcal{L}_{m})$\u0000gravity offers a viable framework for the existence of stable, traversable\u0000wormholes sustained by exotic matter, potentially expanding the landscape of\u0000viable wormhole solutions beyond the confines of GR.","PeriodicalId":501041,"journal":{"name":"arXiv - PHYS - General Relativity and Quantum Cosmology","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142250659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Magnetic Reconnection and Energy Extraction from a Konoplya-Zhidenko rotating non-Kerr black hole 科诺普赖亚-日登科旋转非克尔黑洞的磁再连接与能量提取

arXiv - PHYS - General Relativity and Quantum Cosmology Pub Date : 2024-09-18 DOI: arxiv-2409.11942

Fen Long, Shangyun Wang, Songbai Chen, Jiliang Jing

引用次数: 0

Multi-field TDiff theories for cosmology 宇宙学多场 TDiff 理论

arXiv - PHYS - General Relativity and Quantum Cosmology Pub Date : 2024-09-18 DOI: arxiv-2409.11991

Diego Tessainer, Antonio L. Maroto, Prado Martín-Moruno

引用次数: 0

Field Sources for $f(R,R_{μν})$ Black-Bounce Solutions: The Case of K-Gravity $f(R,R_{μν})$黑弹解的场源：K引力案例

arXiv - PHYS - General Relativity and Quantum Cosmology Pub Date : 2024-09-18 DOI: arxiv-2409.12101

G. Alencar, M. Nilton, Manuel E. Rodrigues, Marcos V. de S. Silva

{"title":"Field Sources for $f(R,R_{μν})$ Black-Bounce Solutions: The Case of K-Gravity","authors":"G. Alencar, M. Nilton, Manuel E. Rodrigues, Marcos V. de S. Silva","doi":"arxiv-2409.12101","DOIUrl":"https://doi.org/arxiv-2409.12101","url":null,"abstract":"In the framework of Simpson-Visser, the search for field sources that produce\u0000black bounces in alternative gravity theories has remained unresolved. In this\u0000paper, the first in a series exploring sources for alternative theories of\u0000gravity, we identify such a source for the $2+1$ dimensional K-gravity black\u0000bounce. The K-gravity black hole is notable for allowing asymptotically locally\u0000flat solutions in lower-dimensional spacetime, yet it possesses curvature\u0000singularities concealed within the event horizon. Using the Simpson-Visser\u0000regularization technique, we eliminate this singularity, constructing\u0000asymptotically locally flat black-bounce solutions in $2+1$ dimensions. We\u0000explore the causal structure of these solutions, identifying the conditions\u0000under which they describe regular black holes or wormholes. By calculating\u0000curvature invariants, we confirm the absence of singularities within the event\u0000horizon. Additionally, we demonstrate that, beyond non-linear electrodynamics,\u0000a non-linear scalar field is required to source the solution. Finally, we\u0000investigate the geodesic structure of this spacetime, analyzing the\u0000trajectories of both massive and massless particles. We also confirm the\u0000existence of circular orbits and assess their stability.","PeriodicalId":501041,"journal":{"name":"arXiv - PHYS - General Relativity and Quantum Cosmology","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142250662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Gravitational waves from primordial black hole isocurvature: the effect of non-Gaussianities 来自原始黑洞等曲率的引力波：非高斯性的影响

arXiv - PHYS - General Relativity and Quantum Cosmology Pub Date : 2024-09-17 DOI: arxiv-2409.11333

Xin-Chen He, Yi-Fu Cai, Xiao-Han Ma, Theodoros Papanikolaou, Emmanuel N. Saridakis, Misao Sasaki

{"title":"Gravitational waves from primordial black hole isocurvature: the effect of non-Gaussianities","authors":"Xin-Chen He, Yi-Fu Cai, Xiao-Han Ma, Theodoros Papanikolaou, Emmanuel N. Saridakis, Misao Sasaki","doi":"arxiv-2409.11333","DOIUrl":"https://doi.org/arxiv-2409.11333","url":null,"abstract":"Ultra-light primordial black holes (PBHs) with masses $M_{rm PBH}<5times\u000010^8mathrm{g}$ can dominate transiently the energy budget of the Universe and\u0000reheat the Universe through their evaporation taking place before Big Bang\u0000Nucleosynthesis. The isocurvature energy density fluctuations associated to the\u0000inhomogeneous distribution of a population of such PBHs can induce an abundant\u0000production of GWs due to second-order gravitational effects. In this work, we\u0000discuss the effect of primordial non-Gaussianity on the clustering properties\u0000of PBHs and study the effect of a clustered PBH population on the spectral\u0000shape of the aforementioned induced GW signal. In particular, focusing on\u0000local-type non-Gaussianity we find a double-peaked GW signal with the amplitude\u0000of the low-frequency peak being proportional to the square of the non-Gaussian\u0000parameter $tau_mathrm{NL}$. Remarkably, depending on the PBH mass $M_{rm\u0000PBH}$ and the initial abundance of PBHs at formation time, i.e.\u0000$Omega_mathrm{PBH,f}$, this double-peaked GW signal can lie well within the\u0000frequency bands of forthcoming GW detectors, namely LISA, ET, SKA and BBO,\u0000hence rendering this signal falsifiable by GW experiments and promoting it as a\u0000novel portal probing the primordial non-Gaussianity.","PeriodicalId":501041,"journal":{"name":"arXiv - PHYS - General Relativity and Quantum Cosmology","volume":"211 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142250726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Assessing the potential of LIGO-India in resolving the Hubble Tension 评估 LIGO-India 在解决哈勃张力方面的潜力

arXiv - PHYS - General Relativity and Quantum Cosmology Pub Date : 2024-09-17 DOI: arxiv-2409.11361

Kanchan Soni, Aditya Vijaykumar, Sanjit Mitra

{"title":"Assessing the potential of LIGO-India in resolving the Hubble Tension","authors":"Kanchan Soni, Aditya Vijaykumar, Sanjit Mitra","doi":"arxiv-2409.11361","DOIUrl":"https://doi.org/arxiv-2409.11361","url":null,"abstract":"Determining the Hubble constant (H0), a fundamental parameter describing\u0000cosmic expansion, remains a challenge due to conflicting measurements from the\u0000early and late universe. Gravitational wave (GW) observations from binary\u0000neutron star (BNS) mergers, with identified host galaxies through\u0000electromagnetic (EM) follow-up, offer an independent method to measure H0.\u0000However, this requires detection of numerous events, which could take decades\u0000with current GW detectors. LIGO-India can dramatically accelerate this effort.\u0000With sensitivity comparable to the existing LIGO detectors, its addition to the\u0000LIGO-Virgo network could increase detected events by 70%. This improvement\u0000nearly doubles when accounting for the detector's 70% duty cycle, increasing\u0000the probability of simultaneous operation of three detectors by a factor of ~2.\u0000We perform end-to-end simulations to estimate triple-coincidence detection\u0000rates and sky localization, considering realistic BNS populations, lightcurves,\u0000and EM observatory specifications. Our findings suggest LIGO-India could\u0000increase BNS events with observed kilonovae by ~2-7 times. The factor of few\u0000improvements in source localization precision with LIGO-India can allow much\u0000deeper EM follow-up campaigns (not considered in the simulations), potentially\u0000increasing the overall rate of detection of EM counterparts by a factor of ~20,\u0000which can have an enormous impact in addressing critical questions in different\u0000areas of astronomy. We evaluate the impact of LIGO-India in the context of H0\u0000measurement and argue that it can cut down the required observation time of\u0000several decades by a factor of few and possibly to just few years with regular\u0000sensitivity upgrades.","PeriodicalId":501041,"journal":{"name":"arXiv - PHYS - General Relativity and Quantum Cosmology","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142250721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Mapping Anisotropies in the Stochastic Gravitational-Wave Background with TianQin 与天琴一起绘制随机引力波背景中的各向异性图

arXiv - PHYS - General Relativity and Quantum Cosmology Pub Date : 2024-09-17 DOI: arxiv-2409.11245

Zhi-Yuan Li, Zheng-Cheng Liang, En-Kun Li, Jian-dong Zhang, Yi-Ming Hu

{"title":"Mapping Anisotropies in the Stochastic Gravitational-Wave Background with TianQin","authors":"Zhi-Yuan Li, Zheng-Cheng Liang, En-Kun Li, Jian-dong Zhang, Yi-Ming Hu","doi":"arxiv-2409.11245","DOIUrl":"https://doi.org/arxiv-2409.11245","url":null,"abstract":"In the milli-Hertz frequency band, stochastic gravitational-wave background\u0000can be composed of both astronomical and cosmological sources, both can be\u0000anisotropic. Numerically depicting these anisotropies can be critical in\u0000revealing the underlying properties of their origins. For the first time, we\u0000perform a theoretical analysis of the constraining ability of TianQin on\u0000multiple moments of the stochastic background. First, we find that with a\u0000one-year operation, for a background with a signal-to-noise ratio of 16,\u0000TianQin can recover the multiple moments up to $l=4$. We also identified a\u0000unique feature of the stochastic background sky map, which is the mirror\u0000symmetry along the fixed orbital plane of TianQin. Thirdly, we explain the\u0000difference in anisotropy recovering ability between TianQin and LISA, by\u0000employing the criteria of the singularity of the covariance matrix (which is\u0000the condition number). Finally, we find that since the different data channel\u0000combinations correspond to different singularities, certain combinations might\u0000have an advantage in stochastic background map-making. We believe that the\u0000findings of this work can provide an important reference to future stochastic\u0000background analysis pipelines. It can also serve as a guideline for designing\u0000better gravitational-wave detectors aiming to decipher anisotropies in the\u0000stochastic background.","PeriodicalId":501041,"journal":{"name":"arXiv - PHYS - General Relativity and Quantum Cosmology","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142250722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

$Λ$CDM Model Extension with Dissipative Dynamics and Sign-Switching Bulk Viscous Pressure 具有耗散动力学和符号转换体积粘性压力的Λ$CDM 模型扩展

arXiv - PHYS - General Relativity and Quantum Cosmology Pub Date : 2024-09-17 DOI: arxiv-2409.10919

Vishnu A Pai, Sarath N, Titus K Mathew

{"title":"$Λ$CDM Model Extension with Dissipative Dynamics and Sign-Switching Bulk Viscous Pressure","authors":"Vishnu A Pai, Sarath N, Titus K Mathew","doi":"arxiv-2409.10919","DOIUrl":"https://doi.org/arxiv-2409.10919","url":null,"abstract":"In this article, we extend the standard $Lambda$CDM model by incorporating\u0000causal viscous dark matter (vDM) modelled using Maxwell-Cattaneo theory and\u0000obtain a novel Hubble parameter solution for the model, which can even be\u0000extended to incorporate both radiation and baryonic matter components. A\u0000detailed and comprehensive analysis of the model is carried out by deriving\u0000theoretical constraints on model parameters, comparing the model with the\u0000latest observational data sets and validating the behaviour of the model under\u0000different thermodynamic laws. Such an in-depth analysis of the model yielded\u0000several intriguing results, like the presence of sign-switching bulk viscous\u0000pressure which aids both, the decelerated expansion in the early universe and\u0000the accelerated expansion in the late universe, possibility of having negative\u0000specific entropy rate in the early Universe while still satisfying the\u0000covariant second law of thermodynamics, and a correlation between relaxation\u0000time parameter and sign-switching redshift. Finally, we propose a unified dark\u0000matter (UDM) interpretation for the dark sector in this model and hence showed\u0000that, under the said UDM interpretation, this model can satisfy the\u0000much-required near equilibrium condition associated with the background\u0000dissipative theory both in the early and late phase of the Universe. Based on\u0000the NEC trend showcased by the model, we conjuncture that the late-accelerating\u0000behaviour of Universe can be viewed as a means for the UDM fluid to attain a\u0000global equilibrium state.","PeriodicalId":501041,"journal":{"name":"arXiv - PHYS - General Relativity and Quantum Cosmology","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142250727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0