Physics of the Dark Universe最新文献

{"title":"Kinetic model for dark energy—dark matter interaction: Scenario for the hubble tension","authors":"Giovanni Montani ,&nbsp;Nakia Carlevaro ,&nbsp;Luis A. Escamilla ,&nbsp;Eleonora Di Valentino","doi":"10.1016/j.dark.2025.101848","DOIUrl":"10.1016/j.dark.2025.101848","url":null,"abstract":"<div><div>We analyze a model for Dark Energy - Dark Matter interaction, based on a decaying process of the former into the latter. The dynamical equations are constructed following a kinetic formulation, which separates the interacting fluctuations from an equilibrium distribution of both species. The emerging dynamical picture consists of coupled equations, which are specialized in the case of a Dark Energy equation of state parameter; we deal with a modified Lambda Cold Dark Matter (<span><math><mi>Λ</mi></math></span>CDM) model, which is investigated versus a possible interpretation of the Hubble tension. Using an optimized set of the model’s free parameters, it can be shown that the obtained Hubble parameter can, in principle, address the tension. We then use the most recent datasets from late Universe sources and compressed information from the Cosmic Microwave Background data to constrain the free parameters and compare the addressed scenario to the standard <span><math><mi>Λ</mi></math></span>CDM model. The study outlines how our proposal is preferred by the data in all cases, based on fit quality, while also alleviating the tension.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"48 ","pages":"Article 101848"},"PeriodicalIF":5.0,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143454132","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}

{"title":"A comprehensive analysis of Barrow holographic Chaplygin gas model reconstruction and its cosmological consequences","authors":"Sanjeeda Sultana ,&nbsp;Chayan Ranjit ,&nbsp;Surajit Chattopadhyay","doi":"10.1016/j.dark.2025.101843","DOIUrl":"10.1016/j.dark.2025.101843","url":null,"abstract":"<div><div>In the current study, we have reconstructed variable modified Chaplygin gas in the Barrow holographic dark energy framework motivated by many recent studies. We have validated the generalized second law of thermodynamics for the reconstructed model. The permissible values of the reconstructed model have been determined by the recent astrophysical and cosmological observational data. The Hubble parameter is presented in terms of the observable parameters and redshift <span><math><mi>z</mi></math></span> and other model parameters. From the Stern data set and joint data set of Stern with BAO and CMB observations, the bounds of the model parameters <span><math><mrow><mo>(</mo><msub><mrow><mi>B</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>,</mo><msub><mrow><mi>Ω</mi></mrow><mrow><mi>b</mi><mi>h</mi><mi>d</mi><mn>0</mn></mrow></msub><mo>)</mo></mrow></math></span> are obtained by the <span><math><msup><mrow><mi>χ</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span> minimization procedure. The best-fit value of the distance modulus <span><math><mrow><mi>μ</mi><mrow><mo>(</mo><mi>z</mi><mo>)</mo></mrow></mrow></math></span> against redshift <span><math><mi>z</mi></math></span> is obtained for the reconstructed model and it is consistent with the SNe Ia union2 sample data.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"48 ","pages":"Article 101843"},"PeriodicalIF":5.0,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143419375","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}

{"title":"Gravastar models in braneworld scenario: The influence of Durgapal-V metric potential","authors":"Sunaiha Naeem ,&nbsp;Arfa Waseem ,&nbsp;Bander Almutairi ,&nbsp;Faisal Javed","doi":"10.1016/j.dark.2025.101849","DOIUrl":"10.1016/j.dark.2025.101849","url":null,"abstract":"<div><div>This study aims to elucidate the nature of isotropic static spherically symmetric gravastars within the framework of braneworld gravity. Focusing on the dimensionally reduced Randall–Sundrum II scenario with positive brane tension, we utilize a physically acceptable Durgapal-V type metric potential that ensures non-singularity and stability. In alignment with the Mazur-Mottola conjecture, we derive the expressions for Durgapal-V parameters by applying junction conditions derived from a Schwarzschild vacuum, excluding a cosmological constant. Our framework envisions the inner area filled with a substance resembling an exotic energy field, while the surrounding layer is described as an ultrarelativistic stiff fluid. Through this model, we analyze multiple physical attributes of gravastars, including spatial dimensions, energy contained in the shell, entropy measurements, surface redshift due to gravitational effects, and the mass of the inner region and its thin envelope. The results provide fruitful insights into gravastars under Durgapal-V metric functions in the braneworld scenario.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"48 ","pages":"Article 101849"},"PeriodicalIF":5.0,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143403085","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}

{"title":"Testing of rotating Einstein-Yang–Mills-Higgs black hole through QPOs","authors":"Asifa Ashraf ,&nbsp;Faisal Javed ,&nbsp;S.K. Maurya ,&nbsp;Phongpichit Channuie ,&nbsp;Arzu Cilli ,&nbsp;Ertan Güdekli","doi":"10.1016/j.dark.2025.101853","DOIUrl":"10.1016/j.dark.2025.101853","url":null,"abstract":"<div><div>We investigate the influence of model parameters on the orbital and epicyclic motion of test particles around a spinning Einstein-Yang–Mills-Higgs black hole. A black hole having four defining parameters is its mass <span><math><mi>M</mi></math></span>, its rotation parameter <span><math><mi>a</mi></math></span>, a constant, <span><math><mi>β</mi></math></span> and the theory parameter <span><math><mi>B</mi></math></span>. Formulas for the specific energy and angular momentum of the circular orbits in an equatorial plane are derived analytically. The stability of the spherical equatorial orbit is also examined using the effective potential method. We obtain analytical formulas for the particle frequencies of the radial, vertical, and orbital oscillations in relation to the properties of the black hole model under consideration. The main characteristics of quasi-periodic oscillations close to the stable circular orbits are discussed. Furthermore, we examine the precessions of Periastron and Lense-Thirring. It is concluded that the parameters of the consider black hole model strongly influence the motion of the particles around the black hole.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"48 ","pages":"Article 101853"},"PeriodicalIF":5.0,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143387318","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}

{"title":"A new generic class of charged stellar structure in extended teleparallel gravity","authors":"M.R. Shahzad ,&nbsp;Liaba Fakhar ,&nbsp;H. Nazar ,&nbsp;Asifa Ashraf ,&nbsp;Awatef Abidi","doi":"10.1016/j.dark.2025.101851","DOIUrl":"10.1016/j.dark.2025.101851","url":null,"abstract":"<div><div>In the present work, we proposed a new class of well-behaved charged spherical stellar models in <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>T</mi><mo>)</mo></mrow></mrow></math></span> gravity. A short review of the formulation of field equations is presented by taking the linear model of torsion function as <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>T</mi><mo>)</mo></mrow><mo>=</mo><mi>α</mi><mi>T</mi><mo>+</mo><mi>β</mi></mrow></math></span>, where <span><math><mi>α</mi></math></span> is the coupling parameter of the theory, which is responsible for the deviation from the slandered General Relativity (<span><math><mrow><mi>G</mi><mi>R</mi></mrow></math></span>) theory and explains the matter field’s tendency to couple with geometry. To obtain a realistic solution to the established field equations we have selected a well-behaved ansatz of generalized Tolman–Kuchowicz (GTK) potential functions and the well-studied MIT bag model equation of state. As an external geometry, we include the Reissner–Nordström solution for matching conditions to identify the unknown constants resulting from the <span><math><mrow><mi>G</mi><mi>T</mi><mi>K</mi></mrow></math></span> metric. The proposed model undergoes comprehensive validation to confirm its viability as a physically consistent compact object within the framework of <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>T</mi><mo>)</mo></mrow></mrow></math></span> gravity. We meticulously analyze two critical parameters: <span><math><mi>α</mi></math></span> and <span><math><mi>n</mi></math></span>, examining their effects on the mass, radius, and overall stability of the stellar configuration. Our investigations reveal that the model demonstrates stable behavior, devoid of singularities, and successfully accounts for a diverse array of observed compact objects in astrophysics. This thorough examination ensures that the model adheres to necessary physical criteria, reinforcing its potential applicability to understanding compact star phenomena.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"48 ","pages":"Article 101851"},"PeriodicalIF":5.0,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143387317","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}

{"title":"Probing gravitational baryogenesis phenomenon in specific modified gravity","authors":"A.D. Alruwaili ,&nbsp;N. Azhar ,&nbsp;A. Jawad ,&nbsp;A.B. Albarrak","doi":"10.1016/j.dark.2025.101842","DOIUrl":"10.1016/j.dark.2025.101842","url":null,"abstract":"<div><div>In this research, we investigate the phenomenon of gravitational baryogenesis and generalized gravitational baryogenesis within the framework of <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>Q</mi><mo>,</mo><mi>B</mi><mo>)</mo></mrow></mrow></math></span> gravity where <span><math><mi>Q</mi></math></span> expresses the non-metricity scalar and <span><math><mi>B</mi></math></span> is the boundary term. To explore this mechanism, we utilize four distinct minimal and non-minimal <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>Q</mi><mo>,</mo><mi>B</mi><mo>)</mo></mrow></mrow></math></span> models and analyze the evolution of the baryon to entropy ratio in relation to a scale factor in the form of a power-law ( <span><math><mrow><mi>a</mi><mo>=</mo><mi>Υ</mi><mspace></mspace><msup><mrow><mi>t</mi></mrow><mrow><mi>γ</mi></mrow></msup></mrow></math></span>, where <span><math><mi>Υ</mi></math></span> and <span><math><mi>γ</mi></math></span> are nonzero constants). By studying the CP-violating interaction terms <span><math><mrow><msub><mrow><mi>∂</mi></mrow><mrow><mi>μ</mi></mrow></msub><mrow><mo>(</mo><mi>Q</mi><mo>+</mo><mi>B</mi><mo>)</mo></mrow></mrow></math></span> and <span><math><mrow><msub><mrow><mi>∂</mi></mrow><mrow><mi>μ</mi></mrow></msub><mi>f</mi><mrow><mo>(</mo><mi>Q</mi><mo>+</mo><mi>B</mi><mo>)</mo></mrow></mrow></math></span>, we derive expressions for the baryon asymmetry and examine its behavior across different cosmological epochs. The results obtained from all four models demonstrate compatibility with current observational data on baryon asymmetry, suggesting that <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>Q</mi><mo>,</mo><mi>B</mi><mo>)</mo></mrow></mrow></math></span> gravity offer a robust explanation for the matter–antimatter imbalance in the universe. Our findings reinforce the potential of this modified gravity theory to extend the understanding of baryogenesis beyond the scope of standard models, offering new insights into early universe cosmology and the mechanisms driving the generation of baryon asymmetry.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"48 ","pages":"Article 101842"},"PeriodicalIF":5.0,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143369841","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}

{"title":"Impact of modified Chaplygin gas on electrically charged thin-shell wormhole models","authors":"M. Yousaf,&nbsp;H. Asad","doi":"10.1016/j.dark.2025.101841","DOIUrl":"10.1016/j.dark.2025.101841","url":null,"abstract":"<div><div>In this study, the possibility of constructing wormhole geometries is explored within the framework of <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>R</mi><mo>,</mo><mi>T</mi><mo>)</mo></mrow></mrow></math></span> gravity, where <span><math><mi>R</mi></math></span> is Ricci scalar and <span><math><mi>T</mi></math></span> represents the trace of the energy–momentum tensor. We employ the Visser cut-and-paste technique to construct thin-shell wormholes by joining two identical copies of the Reissner-Nordström (RN) spacetime which allows the formulation of wormhole geometries by introducing a throat, the boundary of the two spacetime copies, where the stress–energy tensor components are determined using the Lanczos equations. To derive wormhole solutions, our analyses focus on a static, spherically symmetric spacetime and incorporate the modified Chaplygin gas (MCG) equation of state (EoS) as a source of exotic matter. The dynamical equation governing the system is examined under the assumption of small linear perturbations around a static equilibrium state within an isotropic background which is critical in assessing the stability of the wormhole configurations. We present our findings theoretically and graphically, highlighting the behavior of wormhole solutions for various parametric choices of the <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>R</mi><mo>,</mo><mi>T</mi><mo>)</mo></mrow></mrow></math></span> model and the EoS. The results indicate that distinct parameters set yield stable and unstable wormhole solutions, demonstrating the feasibility of maintaining traversable wormhole geometries in this modified gravity framework. Our considered minimally coupling <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>R</mi><mo>,</mo><mi>T</mi><mo>)</mo></mrow></mrow></math></span> gravity model supports a variety of wormhole configurations, some of which can achieve stability under linear perturbations. These findings contribute to the broader understanding of exotic structures in modified theories of gravity and their astrophysical implications.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"48 ","pages":"Article 101841"},"PeriodicalIF":5.0,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143369840","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}

{"title":"The dynamics of cosmic evolution: Insights from bouncing cosmology","authors":"M. Sharif ,&nbsp;M. Zeeshan Gul ,&nbsp;Ahmad Nawaz","doi":"10.1016/j.dark.2025.101839","DOIUrl":"10.1016/j.dark.2025.101839","url":null,"abstract":"<div><div>The primary aim of this work is to explore feasible bouncing cosmological solutions in the framework of <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>Q</mi><mo>,</mo><mi>C</mi><mo>)</mo></mrow></mrow></math></span> gravity, where <span><math><mi>Q</mi></math></span> denotes non-metricity and <span><math><mi>C</mi></math></span> indicates the boundary term. To achieve this, we analyze the dynamics of a Bianchi type-I spacetime with perfect fluid distribution. We consider various functional forms of <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>Q,C</mi><mo>)</mo></mrow></mrow></math></span> theory to assess how this modified gravity framework influences cosmic evolution. Additionally, we examine the dynamics of different cosmological parameters to explore non-singular bounce solutions. We also use linear perturbation to study the stability analysis. Our findings reveal the breach of the null energy conditions, which is required for the existence of viable bounce solutions. The equation of state parameter demonstrates either a quintessence phase or a phantom regime of the universe, demonstrating that the cosmos is undergoing accelerating expansion. This gravitational framework presents a promising alternative to the standard cosmological model, presenting an innovative viewpoint on gravitational interactions and the dynamics of the early universe.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"48 ","pages":"Article 101839"},"PeriodicalIF":5.0,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143349147","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}

{"title":"Running Hubble constant: Evolutionary Dark Energy","authors":"G. Montani ,&nbsp;N. Carlevaro ,&nbsp;M.G. Dainotti","doi":"10.1016/j.dark.2025.101847","DOIUrl":"10.1016/j.dark.2025.101847","url":null,"abstract":"<div><div>We discuss an evolutionary dark energy model, based on the presence of non-equilibrium effects on the dark energy constituents, which are described via a bulk viscosity contribution. We implement the proposed dynamics by the analysis of the 40-bins Type Ia Supernovae (SNe) Pantheon sample data, in order to outline the existence of a running Hubble constant with the redshift. Via a fitting procedure, we determine the value of the additional parameter that our model possesses with respect a standard <span><math><mi>Λ</mi></math></span> Cold Dark Matter (<span><math><mi>Λ</mi></math></span>CDM) scenario. As important result, the evolutionary dark energy proposal seems more appropriate to describe the binned SN analysis with respect to the <span><math><mi>Λ</mi></math></span>CDM Hubble parameter, i.e. a non running value for the Hubble constant over the bins.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"48 ","pages":"Article 101847"},"PeriodicalIF":5.0,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143350671","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}

{"title":"Role of polytropic equation of state through structure scalars in the complex self-gravitating systems","authors":"Bander Almutairi ,&nbsp;M.M.M. Nasir ,&nbsp;T. Ganesan","doi":"10.1016/j.dark.2025.101835","DOIUrl":"10.1016/j.dark.2025.101835","url":null,"abstract":"<div><div>In this article, our aim is to study a novel approach to comprehend the complexity of gravitational objects within the background of polytropic equation of state and Einstein-Gauss–Bonnet approach. Here, we examine the role of the complexity factor in determining whether a system becomes complex or simple. We consider spherically symmetric line element with anisotropic and nonhomogeneous fluid configuration. These scalar parameters are used to examine the characteristic of physical variables, in this way, we choose one scalars as the complexity factor, following Herrera’s approach (Herrera, 2018). In order to find the structure scalars, we introduce the basic formulation of the Riemann tensor and two distinct mass approaches that address the entire energy budget of the system. In order to find the solution of the field equation, two different models are used with the help of vanishing complexity condition.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"48 ","pages":"Article 101835"},"PeriodicalIF":5.0,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143312478","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}