Physics of the Dark Universe最新文献_第4页

Compact stars with color–flavor-locked quark matter in gravity’s rainbow

IF 5 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-03-06 DOI: 10.1016/j.dark.2025.101885

A. Errehymy , K. Boshkayev , A. Banerjee , M. Daoud , N. Alessa , A.-H. Abdel-Aty

{"title":"Compact stars with color–flavor-locked quark matter in gravity’s rainbow","authors":"A. Errehymy , K. Boshkayev , A. Banerjee , M. Daoud , N. Alessa , A.-H. Abdel-Aty","doi":"10.1016/j.dark.2025.101885","DOIUrl":"10.1016/j.dark.2025.101885","url":null,"abstract":"<div><div>The gravity’s rainbow, an alternative gravity theory, postulates that the spacetime background depends on the energy of a test particle. In this scenario, we have investigated the existence of compact stars made of color–flavor locked (CFL) matter at asymptotically high density. Our numerical solutions to the modified TOV equations allow us to display the mass–radius <span><math><mrow><mo>(</mo><mi>M</mi><mo>−</mo><mi>R</mi><mo>)</mo></mrow></math></span> diagram for the given equation of state (EoS). We have further studied how the rainbow functions affect <span><math><mrow><mo>(</mo><mi>M</mi><mo>−</mo><mi>R</mi><mo>)</mo></mrow></math></span> relations and compared them with the GR counterpart. To constrain the permissible values of the parameters appearing in rainbow gravity, we have used the mass and radius measurements from the observed pulsars. We also include constraints obtained from the GW170817 event. Finally, we analyze the static stability, adiabatic index, and sound velocity profiles to strengthen our proposed model for the existence of quark stars in rainbow gravity.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"48 ","pages":"Article 101885"},"PeriodicalIF":5.0,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143577748","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

On the field theoretical description of an alternative model to Generalized Chaplygin Gas and its thermodynamic behaviour

IF 5 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-03-04 DOI: 10.1016/j.dark.2025.101878

Tamal Mukhopadhyay , Banadipa Chakraborty , Ujjal Debnath , Anirudh Pradhan

{"title":"On the field theoretical description of an alternative model to Generalized Chaplygin Gas and its thermodynamic behaviour","authors":"Tamal Mukhopadhyay , Banadipa Chakraborty , Ujjal Debnath , Anirudh Pradhan","doi":"10.1016/j.dark.2025.101878","DOIUrl":"10.1016/j.dark.2025.101878","url":null,"abstract":"<div><div>This paper investigates a newly proposed fluid description of dark energy within the framework of the late-time accelerated expansion of the universe. Our primary objective is to explore the theoretical foundation of the proposed equation of state by establishing its correspondence with well-known scalar field models, such as quintessence, k-essence, and DBI-essence. Through this correspondence, we reconstruct key field parameters, including the scalar field <span><math><mi>ϕ</mi></math></span> and scalar potential <span><math><mrow><mi>V</mi><mrow><mo>(</mo><mi>ϕ</mi><mo>)</mo></mrow></mrow></math></span>, and analyse their evolutionary behaviour across cosmic time. The study also evaluates the model’s physical consistency and cosmological implications by examining fundamental energy conditions—Null Energy Condition (NEC), Dominant Energy Condition (DEC), and Strong Energy Condition (SEC). Furthermore, we conduct a comprehensive stability analysis to ensure the robustness of the model and investigate its thermodynamic properties, including possible phase transitions using entropy and Gibbs free energy. To assess the observational viability of the model, we compare its predictions against recent datasets, including Cosmic Chronometers (CC), Baryon Acoustic Oscillation (BAO), and Supernova Type-Ia from the Pantheon+SH0ES compilation and Union 2.1, as well as recent DESI and DESY5 data. Our analysis demonstrates that the proposed fluid model aligns well with observational constraints, reproduces the late-time acceleration of the universe, and offers a compelling alternative to the standard <span><math><mi>Λ</mi></math></span>CDM model while maintaining consistency with current data.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"48 ","pages":"Article 101878"},"PeriodicalIF":5.0,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143562880","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

Regular Black Hole from gravitational collapse of dust and radiation

IF 5 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-03-03 DOI: 10.1016/j.dark.2025.101881

Vitalii Vertogradov

引用次数: 0

Exploring effective force, trajectories, QPOs and center-of-mass energy around a black hole surrounded by pseudo-isothermal dark matter halo

IF 5 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-03-03 DOI: 10.1016/j.dark.2025.101879

G. Mustafa , Abdelmalek Bouzenada , S.K. Maurya , Saibal Ray , Badr S. Alkahtani , Farruh Atamurotov

{"title":"Exploring effective force, trajectories, QPOs and center-of-mass energy around a black hole surrounded by pseudo-isothermal dark matter halo","authors":"G. Mustafa , Abdelmalek Bouzenada , S.K. Maurya , Saibal Ray , Badr S. Alkahtani , Farruh Atamurotov","doi":"10.1016/j.dark.2025.101879","DOIUrl":"10.1016/j.dark.2025.101879","url":null,"abstract":"<div><div>In this work, we analyze the motion of test particles around a spherically symmetric non-rotating black hole embedded in a pseudo-isothermal dark matter halo, investigating how the black hole mass <span><math><mi>M</mi></math></span>, central halo density <span><math><msub><mrow><mi>ρ</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span> and core radius <span><math><msub><mrow><mi>R</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span> influence particle dynamics. We have used the effective potential approach to evaluate the stability of circular orbits, derive analytical formulas for the specific energy and angular momentum of the test particles, and calculate the innermost stable circular orbit as well as the effective force functioning on the particles. To gain a deeper understanding of orbital behavior, we employ numerical integration to simulate and visualize particle trajectories in the vicinity of the black hole. In addition, we explore epicyclic oscillations near the equatorial plane, derive expressions for radial, vertical, and orbital frequencies, which give some information about motion as perceived by both local and distant observers. Moreover, we have tested the precession of the periastron and evaluated the influence of model parameters on this relativistic phenomenon. We have analyzed high-energy particle collisions within this type of black hole, from which we can easily formulate an analytical equation for the center-of-mass energy. In this context, our results demonstrate that the combined effects of the black hole and the surrounding dark matter halo significantly alter the motion of test particles, influencing their stability, orbital evolution, and collision dynamics.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"48 ","pages":"Article 101879"},"PeriodicalIF":5.0,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143562879","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

Effects of dynamical friction on perturbations for evolving dark energy

IF 5 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-02-28 DOI: 10.1016/j.dark.2025.101871

Francesco Pace , Orlando Luongo , Antonino Del Popolo

{"title":"Effects of dynamical friction on perturbations for evolving dark energy","authors":"Francesco Pace , Orlando Luongo , Antonino Del Popolo","doi":"10.1016/j.dark.2025.101871","DOIUrl":"10.1016/j.dark.2025.101871","url":null,"abstract":"<div><div>We explore the impact of dynamical friction on scales where the linear growth factor and the spherical collapse model can be applied and show its influence on the evolution of perturbations. In particular, considering smooth and clustering dark energy models, we describe the role played by friction by selecting two main hierarchical models, <em>i.e.</em>, the first where the friction term is proportional to the Hubble rate, whereas the second where friction is induced by the dark energy pressure. The second approach generalizes the first and translates the idea that pressure is a general relativistic effect, motivating why friction might arise once barotropic dark energy fluids are considered. The corresponding effects of friction are investigated at the level of linear and nonlinear perturbations, using the formalism of the spherical collapse model. Whilst dynamical friction has very small effects and thus it cannot be excluded <em>a priori</em>, dissipative pressure friction leads to a substantial slow down in the evolution of perturbations. This can be inferred particularly from the halo mass function, for which we also employ corrections due to dark energy clustering. To this end, in order to discern detectable deviations from the standard cosmological model, we thus highlight where dissipation effects might play a significant role at large scales.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"48 ","pages":"Article 101871"},"PeriodicalIF":5.0,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143562878","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

Probing thermodynamics of Einstein–Maxwell scalar black hole through exponential corrected entropy

IF 5 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-02-28 DOI: 10.1016/j.dark.2025.101875

Shamaila Rani , Ayesha Siddiqa , Amna Mir , Mohammad Mahtab Alam , Hussnain Raza , Sanjar Shaymatov

引用次数: 0

Testing quantum Einstein gravity via epicyclic oscillations around rotating black hole

IF 5 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-02-27 DOI: 10.1016/j.dark.2025.101877

Asifa Ashraf , Faisal Javed , Allah Ditta , Phongpichit Channuie , Farruh Atamurotov , A.S. Shflot , Muhammad Yousaf Malik

{"title":"Testing quantum Einstein gravity via epicyclic oscillations around rotating black hole","authors":"Asifa Ashraf , Faisal Javed , Allah Ditta , Phongpichit Channuie , Farruh Atamurotov , A.S. Shflot , Muhammad Yousaf Malik","doi":"10.1016/j.dark.2025.101877","DOIUrl":"10.1016/j.dark.2025.101877","url":null,"abstract":"<div><div>We consider the motion of test particles moving around a rotating black hole in the framework of quantum gravity and examine the influence of parameters of the model on the test particle motion. The black hole solution is characterized by four parameters, the mass <span><math><mi>M</mi></math></span> of the black hole, the rotation parameter <span><math><mi>a</mi></math></span> of the black hole, and two parameters <span><math><mi>α</mi></math></span> and <span><math><mi>β</mi></math></span> of the quantum theory of gravity. We discuss the stability of equatorial circular orbits, and derive analytical solutions for the angular momentum and the corresponding energy for equatorial circular orbits. We also discuss the effective force acting on test particles. Furthermore, we discuss the epicyclic oscillations and derive the analytical expressions for the orbital, radial, and vertical frequencies as a function of the parameters of the underlying model. We also examine the Periastron frequency and Lense–Thirring precession. It is shown that the motion of particles around a rotating black hole in the background of quantum gravity is influenced by the black hole parameters.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"48 ","pages":"Article 101877"},"PeriodicalIF":5.0,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143519541","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

Impact of equation of state on fluid spheres in Finselarian gravity 状态方程对芬塞尔引力中流体球体的影响

IF 5 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-02-26 DOI: 10.1016/j.dark.2025.101873

Allah Ditta , Rubab Manzoor , Faisal Javed , Muhammad Aslam , Muhammad Yousaf Malik , Guzalxon Belalova

{"title":"Impact of equation of state on fluid spheres in Finselarian gravity","authors":"Allah Ditta , Rubab Manzoor , Faisal Javed , Muhammad Aslam , Muhammad Yousaf Malik , Guzalxon Belalova","doi":"10.1016/j.dark.2025.101873","DOIUrl":"10.1016/j.dark.2025.101873","url":null,"abstract":"<div><div>The motivation behind this article is studying the configurations of compact bodies under the effects of Finselarian gravity in spherical symmetric spacetime coordinates. To examine the effects of gravity on compact stellar configurations, we use the Tolman–Kuchowicz components for spherical symmetric spacetime. We use the linear equation of state to find the function <span><math><mrow><msubsup><mrow><mi>u</mi></mrow><mrow><mn>0</mn></mrow><mrow><msup><mrow></mrow><mrow><mo>′</mo></mrow></msup></mrow></msubsup><mrow><mo>(</mo><mi>r</mi><mo>)</mo></mrow></mrow></math></span> involved in Finselsian gravity. We analyze the configurations using the data for the mass and radius for compact candidates <span><math><mrow><mi>H</mi><mi>e</mi><mi>r</mi><mspace></mspace><mi>X</mi><mo>−</mo><mn>1</mn><mo>,</mo><mspace></mspace><mi>S</mi><mi>M</mi><mi>C</mi><mspace></mspace><mi>X</mi><mo>−</mo><mn>1</mn><mo>,</mo><mspace></mspace><mi>L</mi><mi>M</mi><mi>C</mi><mspace></mspace><mi>X</mi><mo>−</mo><mn>4</mn><mo>,</mo><mspace></mspace><mi>C</mi><mi>e</mi><mi>n</mi><mspace></mspace><mi>X</mi><mo>−</mo><mn>3</mn></mrow></math></span>. All the star structures that are considered here are stable and ideally free of a central singularity. A detailed graphical investigation reveals that several physical properties, such as density, pressures, sound speeds, TOV forces, mass function, and compactification implemented in celestial formations are critical to their formation. Moreover, we conclude that our stellar models behave well and are acceptable.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"48 ","pages":"Article 101873"},"PeriodicalIF":5.0,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143519539","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

Particles acceleration by Bocharova–Bronnikov–Melnikov–Bekenstein black hole

IF 5 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-02-26 DOI: 10.1016/j.dark.2025.101876

Bobur Turimov , Sulton Usanov , Yokubjon Khamroev

{"title":"Particles acceleration by Bocharova–Bronnikov–Melnikov–Bekenstein black hole","authors":"Bobur Turimov , Sulton Usanov , Yokubjon Khamroev","doi":"10.1016/j.dark.2025.101876","DOIUrl":"10.1016/j.dark.2025.101876","url":null,"abstract":"<div><div>We have studied the motion of massive particles under the influence of scalar and gravitational fields, with particular emphasis on the BBMB black hole. It has been shown that the radius of the innermost stable circular orbit (ISCO) and marginally bound orbit are significantly affected by the scalar coupling parameter. We study the energy efficiency of thin accretion disks around BBMB black holes, showing that the efficiency decreases for positive <span><math><msub><mrow><mi>g</mi></mrow><mrow><mi>s</mi></mrow></msub></math></span> and increases for negative <span><math><msub><mrow><mi>g</mi></mrow><mrow><mi>s</mi></mrow></msub></math></span>, with a maximum of approximately 30% for specific <span><math><msub><mrow><mi>g</mi></mrow><mrow><mi>s</mi></mrow></msub></math></span> values. We derive analytical expressions for the angular and linear velocities of orbiting particles, highlighting their dependence on <span><math><msub><mrow><mi>g</mi></mrow><mrow><mi>s</mi></mrow></msub></math></span>. The photon sphere is shown to be independent of <span><math><msub><mrow><mi>g</mi></mrow><mrow><mi>s</mi></mrow></msub></math></span>, but the linear velocity at the ISCO position varies significantly, with massive particles behaving like ultra-relativistic particles near the black hole under scalar field influence. Additionally, we examine the center-of-mass energy (CME) of colliding particles near the BBMB black hole, showing that the scalar field can lead to infinitely high CME near the horizon, consistent with the BSW process. Astrophysical implications include CME values reaching <span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>20</mn></mrow></msup><mspace></mspace><mi>eV</mi></mrow></math></span>, comparable to the energies of ultra-high-energy cosmic rays (UHECR).</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"48 ","pages":"Article 101876"},"PeriodicalIF":5.0,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143508373","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

Exploring Hu–Sawicki gravity through circular motion with trajectories and QPOs testing around a black hole

IF 5 2区物理与天体物理

Physics of the Dark Universe Pub Date : 2025-02-25 DOI: 10.1016/j.dark.2025.101874

Asifa Ashraf , Abdelmalek Bouzenada , S.K. Maurya , Awad A. Ibraheem , Batuhan ÇİL , Ertan Güdekli , Farruh Atamurotov

{"title":"Exploring Hu–Sawicki gravity through circular motion with trajectories and QPOs testing around a black hole","authors":"Asifa Ashraf , Abdelmalek Bouzenada , S.K. Maurya , Awad A. Ibraheem , Batuhan ÇİL , Ertan Güdekli , Farruh Atamurotov","doi":"10.1016/j.dark.2025.101874","DOIUrl":"10.1016/j.dark.2025.101874","url":null,"abstract":"<div><div>Focusing on the influence of the model parameters on particle motion, we investigate the dynamics of test particles around a spherically symmetric, non-rotating black hole within the framework of Hu–Sawicki gravity. The black hole is characterized by four parameters: its mass <span><math><mi>M</mi></math></span>, two dimensionless parameters <span><math><mi>α</mi></math></span> and <span><math><mi>β</mi></math></span>, and a mass scale parameter <span><math><mi>m</mi></math></span>. To analyze the stability of spherical orbits, we employ the effective potential approach, deriving analytical expressions for the energy and angular momentum of test particles as functions of the black hole parameters. In this context, we tested the effective forces acting on the particles and determined the innermost stable circular orbits. To gain further insight into particle trajectories, we numerically integrate the equations of motion. In addition, we investigate epicyclic oscillations near the equatorial plane, obtaining analytical expressions for the radial, vertical, and orbital frequencies, as well as the frequency of periastron precession. Also, we examine particle collisions near the black hole horizon and compute the center-of-mass energy of such events. Our findings demonstrate that the black hole parameters significantly influence particle dynamics, revealing intriguing effects on orbital stability and energetic interactions.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"48 ","pages":"Article 101874"},"PeriodicalIF":5.0,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143519540","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