Physics of the Dark Universe最新文献_第9页

Ultralight black holes as sources of high-energy particles 超轻黑洞是高能粒子的来源

IF 6.4 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-07-28 DOI: 10.1016/j.dark.2025.102034

Michael Zantedeschi , Luca Visinelli

{"title":"Ultralight black holes as sources of high-energy particles","authors":"Michael Zantedeschi , Luca Visinelli","doi":"10.1016/j.dark.2025.102034","DOIUrl":"10.1016/j.dark.2025.102034","url":null,"abstract":"<div><div>The <em>memory burden</em> effect, the idea that the amount of information stored within a system contributes to its stabilization, is particularly relevant for systems with a large information storage capacity, such as black holes. In these objects, the evaporation process halts, at the latest, once approximately half of the initial mass has been radiated away. As a result, light primordial black holes (PBHs) with mass <span><math><mrow><msub><mrow><mi>m</mi></mrow><mrow><mi>PBH</mi></mrow></msub><mo>≲</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>15</mn></mrow></msup><mspace></mspace><mi>g</mi></mrow></math></span>, which are traditionally assumed to have fully evaporated by the present time, may instead survive and constitute viable dark matter candidates. Ongoing mergers of such PBHs would give rise to “young” black holes that resume their evaporation, emitting ultrahigh-energy particles potentially detectable by current experiments. The resulting emission spectrum would be thermal across all Standard Model particle species, offering a clear and distinctive signature. We demonstrate that, if the memory burden effect activates after PBHs have lost around half of their initial mass, current measurements of the neutrino flux at Earth place strong constraints on such dark matter candidates for <span><math><mrow><msub><mrow><mi>m</mi></mrow><mrow><mi>PBH</mi></mrow></msub><mo>≲</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>9</mn></mrow></msup><mspace></mspace><mi>g</mi></mrow></math></span>. This suggests that the memory burden must set in at earlier stages of evaporation. Unlike existing bounds, our results depend solely on the mass of the remnant, and not on model-dependent details of the stabilized phase. We also discuss the potential for refining these constraints through observations of gamma rays, cosmic rays, and gravitational waves.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"49 ","pages":"Article 102034"},"PeriodicalIF":6.4,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144721923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dark energy era with a resolution of Hubble tension in generalized entropic cosmology 广义熵宇宙学中具有哈勃张力分辨率的暗能量时代

IF 6.4 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-07-28 DOI: 10.1016/j.dark.2025.102037

Priyanka Adhikary , Sudipta Das , Sergei D. Odintsov , Tanmoy Paul

引用次数: 0

Constraints on the simultaneous variation of the fine structure constant and the electron mass in light of DESI BAO data 基于DESI BAO数据的精细结构常数和电子质量同步变化的约束

IF 6.4 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-07-28 DOI: 10.1016/j.dark.2025.102035

Yo Toda , Osamu Seto

{"title":"Constraints on the simultaneous variation of the fine structure constant and the electron mass in light of DESI BAO data","authors":"Yo Toda , Osamu Seto","doi":"10.1016/j.dark.2025.102035","DOIUrl":"10.1016/j.dark.2025.102035","url":null,"abstract":"<div><div>We study the cosmological constraints of the time variation of the electron mass <span><math><msub><mrow><mi>m</mi></mrow><mrow><mi>e</mi></mrow></msub></math></span> and the fine-structure constant <span><math><mi>α</mi></math></span>, using data of cosmic microwave background, supernovae light curve and baryon acoustic oscillation (BAO) data including the recent DESI BAO DR2 measurements. The results are slightly depending on the BAO data set included in the analysis. The latest DESI BAO DR2 data strongly indicates that <span><math><msub><mrow><mi>m</mi></mrow><mrow><mi>e</mi></mrow></msub></math></span> or <span><math><mi>α</mi></math></span> is slightly larger than the previous data from 6DF+SDSS and DESI BAO DR1. We also compare the varying <span><math><msub><mrow><mi>m</mi></mrow><mrow><mi>e</mi></mrow></msub></math></span> model, the varying <span><math><mi>α</mi></math></span> model, and the simultaneous variation of <span><math><msub><mrow><mi>m</mi></mrow><mrow><mi>e</mi></mrow></msub></math></span> and <span><math><mi>α</mi></math></span>. When considering the Hubble tension, a larger electron mass is the most promising option and the variation of the fine-structure constants does not alleviate the tension.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"49 ","pages":"Article 102035"},"PeriodicalIF":6.4,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144781474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Black hole solutions in Cotton gravity coupled to nonlinear electrodynamics 非线性电动力学耦合的Cotton引力黑洞解

IF 6.4 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-07-28 DOI: 10.1016/j.dark.2025.102028

Ednaldo L.B. Junior , José Tarciso S.S. Junior , Francisco S.N. Lobo , Manuel E. Rodrigues , Luís F. Dias da Silva , Henrique A. Vieira

{"title":"Black hole solutions in Cotton gravity coupled to nonlinear electrodynamics","authors":"Ednaldo L.B. Junior , José Tarciso S.S. Junior , Francisco S.N. Lobo , Manuel E. Rodrigues , Luís F. Dias da Silva , Henrique A. Vieira","doi":"10.1016/j.dark.2025.102028","DOIUrl":"10.1016/j.dark.2025.102028","url":null,"abstract":"<div><div>The framework of General Relativity (GR) has recently been expanded through the introduction of Cotton Gravity (CG), a theoretical extension proposed by J. Harada. This modified approach integrates the Cotton tensor into the gravitational field equations, naturally encompassing all conventional GR solutions while allowing the cosmological constant to emerge as an integration constant. In this study, we delve into the implications of CG when coupled with nonlinear electrodynamics (NLED), constructing and analyzing three distinct static, spherically symmetric configurations. Our investigation centers on the horizon structure, metric characteristics, and the underlying NLED Lagrangian density of each model. We also confront the theoretical predictions with observational data by comparing the calculated shadow radii of these solutions to constraints imposed by the Event Horizon Telescope’s (EHT) measurements of Sgr A*. The results reveal an extensive spectrum of spacetime geometries, ranging from multi-horizon structures to naked singularities. Furthermore, the agreement between the predicted shadow sizes and EHT observations reinforces the viability of these models in describing the astrophysical image of Sgr A* within certain parameter bounds.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"49 ","pages":"Article 102028"},"PeriodicalIF":6.4,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144738924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thermodynamic insights into Joule–Thomson expansion, particle dynamics, and emission energy of AdS black holes in Horndeski theory 霍恩德斯基理论中焦耳-汤姆逊膨胀、粒子动力学和AdS黑洞发射能量的热力学见解

IF 6.4 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-07-28 DOI: 10.1016/j.dark.2025.102014

Enhua Dai , Faisal Javed , Arfa Waseem , Moataz Alosaimi , Rana Muhammad Zulqarnain

{"title":"Thermodynamic insights into Joule–Thomson expansion, particle dynamics, and emission energy of AdS black holes in Horndeski theory","authors":"Enhua Dai , Faisal Javed , Arfa Waseem , Moataz Alosaimi , Rana Muhammad Zulqarnain","doi":"10.1016/j.dark.2025.102014","DOIUrl":"10.1016/j.dark.2025.102014","url":null,"abstract":"<div><div>This study examines the characteristics and dynamics of AdS black holes under Horndeski theory, highlighting the consequences of critical factors on the thermodynamical features, the innermost stable circular orbit and emission energy. Interestingly, the Schwarzschild horizon radius is observed to shrink in the presence of the Horndeski theory parameter <span><math><mi>β</mi></math></span>. The thermodynamic properties are examined by Joule–Thomson expansions, highlighting specific cooling and heating eras inside the black hole phase space. Furthermore, we analyze the effective potential that determines particle motion, emphasizing the stability of orbits and the impact of angular momentum. We examine the innermost stable circular orbit radius concerning black hole mass and the parameter <span><math><mi>β</mi></math></span>, demonstrating an inward displacement of the innermost stable circular orbit as <span><math><mi>β</mi></math></span> increases. The test particles exhibit periodic motion between the fixed points when they move about the fixed points or escape to infinity when they are outside of the fixed points. Our results demonstrate that the emission energy reaches its maximum at higher frequencies, with marked reductions in the range <span><math><mi>β</mi></math></span> and an increase in mass, indicating substantial implications for forthcoming observational investigations of black holes. This study advances the comprehension of black hole phenomena within modified gravity theories and establishes a basis for further investigating their complex behaviors in astrophysical settings.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"49 ","pages":"Article 102014"},"PeriodicalIF":6.4,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144781484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A model-independent measurement of the expansion and growth rates from BOSS using the FreePower method 使用FreePower方法对BOSS的扩张和增长率进行模型独立测量

IF 6.4 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-07-28 DOI: 10.1016/j.dark.2025.102033

Adrian P. Schirra , Miguel Quartin , Luca Amendola

引用次数: 0

Reconstructing square-law k-inflation from Planck data 从普朗克数据重建平方定律k-暴胀

IF 6.4 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-07-26 DOI: 10.1016/j.dark.2025.102039

Ming Liu , Tong-Yu He , Bohai Chen , Zhan-Wen Han , Rong-Jia Yang

引用次数: 0

Constraining Horˇava–Lifshitz gravity with late-time cosmology 用晚时间宇宙学约束霍尔瓦-利夫希茨引力

IF 6.4 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-07-26 DOI: 10.1016/j.dark.2025.102030

Amit Samaddar, S. Surendra Singh

{"title":"Constraining Horˇava–Lifshitz gravity with late-time cosmology","authors":"Amit Samaddar, S. Surendra Singh","doi":"10.1016/j.dark.2025.102030","DOIUrl":"10.1016/j.dark.2025.102030","url":null,"abstract":"<div><div>This analysis probes the cosmic acceleration phenomenon in the framework of Ho<span><math><mover><mrow><mi>r</mi></mrow><mrow><mo>ˇ</mo></mrow></mover></math></span>ava–Lifshitz (HL) gravity by featuring a novel parametric formulation of the deceleration parameter, <span><math><mrow><mi>q</mi><mrow><mo>(</mo><mi>z</mi><mo>)</mo></mrow><mo>=</mo><msub><mrow><mi>q</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>+</mo><mfrac><mrow><msub><mrow><mi>q</mi></mrow><mrow><mn>1</mn></mrow></msub><mi>z</mi></mrow><mrow><mn>1</mn><mo>+</mo><mi>l</mi><mi>n</mi><mrow><mo>(</mo><mn>1</mn><mo>+</mo><mi>z</mi><mo>)</mo></mrow></mrow></mfrac></mrow></math></span>. We evaluate the Hubble parameter to perform the MCMC analysis in order to refine the model parameters with the Hubble, BAO and Pantheon＋SH0ES datasets. Our investigation reveals optimal estimates <span><math><mrow><msub><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>≈</mo><mn>72</mn><mo>.</mo><mn>9</mn></mrow></math></span> km/s/Mpc and a present deceleration parameter <span><math><mrow><msub><mrow><mi>q</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>≈</mo><mo>−</mo><mn>0</mn><mo>.</mo><mn>57</mn></mrow></math></span>. The evolution of energy density and pressure supports this result, with the EoS parameter <span><math><mi>ω</mi></math></span> which shows transition from a stiff-fluid-like phase at early times to a cosmological constant-like behavior at late times. The persistent violation of the SEC across redshifts solidifies the position of dark energy as the driving force behind cosmic evolution. These observations further establish Ho<span><math><mover><mrow><mi>r</mi></mrow><mrow><mo>ˇ</mo></mrow></mover></math></span>ava–Lifshitz gravity as a promising theoretical framework for explaining the universe’s accelerating expansion at late times.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"49 ","pages":"Article 102030"},"PeriodicalIF":6.4,"publicationDate":"2025-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144721971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Constraining big bang nucleosynthesis in f(T,B) gravity through observational analysis 通过观测分析约束f（T，B）重力下的大爆炸核合成

IF 6.4 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-07-25 DOI: 10.1016/j.dark.2025.102023

Abdul Malik Sultan , Maryam Fatima , Jackson Levi Said , Aliya Batool

引用次数: 0

Circular orbits and accretion disk around a deformed-Schwarzschild black hole in loop quantum gravity 环量子引力中变形史瓦西黑洞周围的圆形轨道和吸积盘

IF 5 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-07-25 DOI: 10.1016/j.dark.2025.102027

Kourosh Nozari , Sara Saghafi , Milad Hajebrahimi , Kimet Jusufi

{"title":"Circular orbits and accretion disk around a deformed-Schwarzschild black hole in loop quantum gravity","authors":"Kourosh Nozari , Sara Saghafi , Milad Hajebrahimi , Kimet Jusufi","doi":"10.1016/j.dark.2025.102027","DOIUrl":"10.1016/j.dark.2025.102027","url":null,"abstract":"<div><div>In this paper, we study the motion of neutral and electrically charged particles in the vicinity of a deformed-Schwarzschild black hole inspired by Loop Quantum Gravity (LQG). To examine the motion of an electrically charged test particle, we propose an expression for electromagnetic 4-potential that contains the impacts of loop quantum gravity. This electromagnetic 4-potential satisfies approximately the covariant Maxwell’s equations to first order in the loop quantum effects. We explore the effects of the loop quantum correction parameter on the particle geodesics. We investigate the innermost stable circular orbits (ISCOs) for both neutral and electrically charged particles in detail, demonstrating that the loop quantum parameter significantly influences on the ISCO radius, causing it to shrink. Finally, we explore the accretion disk around the loop quantum black hole. We delve into the electromagnetic radiation flux, temperature, differential luminosity, and the spectral luminosity as radiation properties of the accretion disk in detail. We show that the loop quantum correction parameter shifts the profile of the electromagnetic flux and accretion disk temperature towards the central object, leading to a slight increase in these quantities.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"49 ","pages":"Article 102027"},"PeriodicalIF":5.0,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144714100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0