Physics of the Dark Universe最新文献_第5页

Parameter extraction of the stochastic gravitational wave background with peak-like templates in millihertz 以毫赫为单位的类峰模板随机引力波背景参数提取

IF 6.4 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

Physics of the Dark Universe

Pub Date : 2026-02-01 Epub Date: 2026-01-14 DOI: 10.1016/j.dark.2026.102217

Heng-Sen Jiao , Hong-Bo Jin , Yun-Long Zhang

We investigate a framework for extracting parameters of stochastic gravitational wave background (SGWB) with peak-like templates in the millihertz frequency band, and we analyze transient contamination effects on parameter reconstruction. We present the spectrum and spectrogram under different conditions and provide the results of parameter reconstruction. Using templates from the early universe, we demonstrate that the peak-like templates outperform the broken power law (BPL) templates in power-law exponents recovery and peak frequency localization. The reconstruction results obtained using data from Fast Fourier Transform (FFT) are better than those obtained using data from Short-Time Fourier Transform (STFT) which is based on the spectrogram. For the single-peak(SP) template, the estimation accuracy of the exponent and peak frequency surpasses that of the BPL template by an order of magnitude, but it demonstrates less precision in amplitude estimation compared to the BPL template. Regarding the double-peak template, parameter estimation results derived from the FFT methodology consistently outperform those obtained using STFT. Nevertheless, transient signals exhibit a detrimental impact on parameter estimation precision, causing errors to increase by an order of magnitude, particularly in multi-peak scenarios. This framework provides an example of using templates to analyze data from space-based gravitational wave detectors.

研究了一种基于毫赫频带类峰模板的随机引力波背景参数提取框架，并分析了瞬态污染对参数重建的影响。给出了不同条件下的光谱和谱图，并给出了参数重建的结果。使用来自早期宇宙的模板，我们证明了类峰模板在幂律指数恢复和峰值频率定位方面优于破幂律模板。利用快速傅里叶变换（FFT）得到的重建结果优于基于谱图的短时傅里叶变换（STFT）得到的重建结果。对于单峰（SP）模板，指数和峰值频率的估计精度比BPL模板高出一个数量级，但其幅度估计精度低于BPL模板。对于双峰模板，FFT方法得到的参数估计结果始终优于STFT方法得到的结果。然而，瞬态信号对参数估计精度有不利影响，导致误差增加一个数量级，特别是在多峰情况下。该框架提供了一个使用模板分析天基引力波探测器数据的示例。

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引用次数: 0

Gravitational lensing in a Kerr black hole within quantum Einstein gravity 量子爱因斯坦引力下克尔黑洞中的引力透镜

IF 6.4 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

Physics of the Dark Universe

Pub Date : 2026-02-01 Epub Date: 2025-12-13 DOI: 10.1016/j.dark.2025.102191

Chen-Hao Xie, Yu Zhang, Bo-Li Liu, Peng-Fei Duan, Yu-Li Lou

The detailed study of the strong gravitational lensing of a Kerr black hole within quantum Einstein gravity (QEG) is performed. We calculate the photon sphere, the deflection angle of light, and observables on the equatorial plane under the strong deflection limit in a vacuum. The presence of quantum effects reduces the radius of the photon sphere, the light deflection angle, the ratio of magnification, the positions of relativistic images, and the time delays on the same side of the lens. However, it increases the separations, and the time delays on the opposite side of the lens. By modeling M87* and Sgr A* as the Kerr black hole within QEG, we find that the time delays are more significant in M87*, while other observables are more pronounced in Sgr A*. Furthermore, we consider the influence of plasma on the gravitational lensing effect. Plasma causes an additional deflection of light, increasing the ratio of magnification, image positions and the time delays, but decreasing the separations. More importantly, we calculate the time delays under the strong deflection limit in the presence of plasma and find that they increase with higher plasma concentrations. Finally, we calculate the weak deflection angle in the weak deflection limit. Our research may be helpful for evaluating the observational imprints of quantum effects on light propagation, as well as the influence of plasma around black holes on gravitational lensing.

对量子爱因斯坦引力（QEG）下克尔黑洞的强引力透镜进行了详细的研究。我们计算了真空中强偏转极限下的光子球、光的偏转角和赤道面上的观测值。量子效应的存在降低了光子球的半径、光的偏转角、放大倍率、相对论性像的位置以及透镜同侧的时间延迟。然而，它增加了分离，并在镜头的另一边的时间延迟。通过将M87*和Sgr A*作为QEG中的Kerr黑洞进行建模，我们发现M87*中的时间延迟更为显著，而Sgr A*中的其他观测值更为明显。此外，我们还考虑了等离子体对引力透镜效应的影响。等离子体引起额外的光偏转，增加了放大倍率、图像位置和时间延迟，但减少了分离。更重要的是，我们计算了等离子体存在时在强偏转极限下的时间延迟，发现它们随着等离子体浓度的增加而增加。最后，计算了弱挠度极限下的弱挠度角。我们的研究可能有助于评估量子效应对光传播的观测印记，以及黑洞周围等离子体对引力透镜的影响。

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引用次数: 0

Quasi-homologous evolution of dynamical relativistic stars in nonmetricity-induced gravity 非规度引力下动态相对论恒星的准同源演化

IF 6.4 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

Physics of the Dark Universe

Pub Date : 2026-02-01 Epub Date: 2025-12-12 DOI: 10.1016/j.dark.2025.102190

S. Khan , Mohammad Alshammari , Othman Abdullah Almatroud , Z. Yousaf

The use of nonmetricity for modeling self-gravitational stellar fluids has become a compelling topic in relativistic astrophysics. In this respect, this study explores some viable non-static compact stellar configurations within the principles of linear and non-linear models of

f (Q)

theory. In particular, we formulate anisotropic, self-gravitational models (both dissipative and non-dissipative) using the well-motivated relativistic constraints known as the complexity-free configuration, along with the quasi-homologous condition. The resulting compact star models reveal important outcomes for the physical characteristics and evolution of dynamical, compact models exhibiting anisotropic stresses and non-uniform density distributions. Our work provides a fresh perspective on the development of highly dense matter objects under non-Riemannian geometrical influences by exploring the interaction between anisotropy, nonmetricity, quasi-homologous symmetry, and the complexity factor.

利用非规性来模拟自引力恒星流体已成为相对论天体物理学中一个引人注目的话题。在这方面，本研究在f(Q)理论的线性和非线性模型的原则下探索了一些可行的非静态致密恒星构型。特别是，我们利用被称为无复杂性配置的良好激发的相对论约束以及准同源条件，制定了各向异性的自引力模型（包括耗散和非耗散）。由此产生的致密恒星模型揭示了具有各向异性应力和非均匀密度分布的动态致密模型的物理特征和演化的重要结果。我们的工作通过探索各向异性、非度量性、准同源对称性和复杂性因素之间的相互作用，为非黎曼几何影响下高密度物质物体的发展提供了一个新的视角。

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引用次数: 0

A remedy of the trans-Planckian censorship problem with smooth slow-roll to power-law inflation transitions in scalar field theory 标量场理论中平滑慢滚到幂律膨胀跃迁的跨普朗克审查问题的补救

IF 6.4 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

Physics of the Dark Universe

Pub Date : 2026-02-01 Epub Date: 2026-01-28 DOI: 10.1016/j.dark.2026.102236

S.D. Odintsov , V.K. Oikonomou

It is known that if the standard slow-roll inflation is followed by a power-law inflationary regime, then the trans-Planckian modes may be safely be contained in the Hubble horizon and never exit it during inflation. In this work we investigate how to realize a smooth transition between a slow-roll and a power-law inflationary regime in the context of single scalar field inflation. As we show it is possible to realize such a smooth transition by generalizing the kinetic energy of single scalar field in the form

{\dot{ϕ}}^{2} = β (ϕ) V (ϕ)

, where β(ϕ) is some appropriate function of the scalar field. Using two distinct approaches we show that it is possible to realize a smooth transition from a slow-roll to a power-law inflationary regime, and the two approaches produce identical results regarding the slow-roll regime. Also we show that the slow-roll regime is quite short, about N ∼ 30 e-foldings, with the flatness and horizon problems being solved with the synergistic effect of the two inflationary patches. The slow-roll era is found to be compatible with the Atacama Cosmology Telescope data.

众所周知，如果标准的慢滚暴胀遵循幂律暴胀制度，那么跨普朗克模式可能被安全地包含在哈勃视界中，并且在暴胀期间永远不会退出它。在这项工作中，我们研究了如何在单标量场暴胀的情况下实现慢滚和幂律暴胀之间的平滑过渡。正如我们所展示的，通过将单个标量场的动能推广为φ˙2=β(φ)V（φ）的形式，可以实现这样的平滑过渡，其中β(φ)是标量场的某个适当函数。使用两种不同的方法，我们表明有可能实现从慢滚到幂律暴胀制度的平稳过渡，并且两种方法对于慢滚制度产生相同的结果。我们还表明，慢滚状态非常短，大约N ~ 30个电子折叠，平面和视界问题在两个暴胀斑块的协同作用下得到解决。慢滚时代被发现与阿塔卡马宇宙望远镜的数据兼容。

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引用次数: 0

Gravitational waves from type-I strings in a neutrino mass model 中微子质量模型中i型弦的引力波

IF 6.4 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

Physics of the Dark Universe

Pub Date : 2026-02-01 Epub Date: 2026-01-07 DOI: 10.1016/j.dark.2025.102204

Adeela Afzal

In this work, we propose a novel realization of type-I cosmic strings arising from the spontaneous breaking of an extended gauge symmetry

S U {(2)}_{R} \times U {(1)}_{B - L}

in the context of a low-scale split seesaw mechanism for neutrino mass generation. We demonstrate that the split seesaw framework, which explains the smallness of neutrino masses, naturally motivates a small scalar self-coupling λ. This intrinsically links the neutrino mass generation mechanism to the formation of type-I cosmic strings, where the gauge coupling dominates over the scalar self-coupling (β ≡ λ/(2g²) < 1). We explore the cosmological implications of these strings, including their gravitational wave signatures that are testable in current and future experiments. Our findings establish a compelling and testable connection between neutrino mass generation and cosmic string phenomenology in an underexplored region of parameter space.

在这项工作中，我们提出了一种新的实现，即在中微子质量产生的低尺度分裂跷跷板机制的背景下，由扩展规范对称SU(2)R×U(1)B−L的自发断裂产生的i型宇宙弦。我们证明了分裂跷跷板框架，这解释了中微子质量的小，自然地激发了一个小的标量自耦合λ。这内在地将中微子质量产生机制与i型宇宙弦的形成联系起来，其中规范耦合支配着标量自耦合（β ≡ λ/(2g2) <； 1）。我们探索这些弦的宇宙学含义，包括它们的引力波特征，这些特征可以在当前和未来的实验中测试。我们的发现建立了一个令人信服的和可测试的中微子质量产生和宇宙弦现象之间的联系，在一个未被探索的参数空间区域。

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引用次数: 0

Exploring cosmological constraints on galaxy formation time 探索星系形成时间的宇宙学限制

IF 6.4 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

Physics of the Dark Universe

Pub Date : 2026-02-01 Epub Date: 2026-01-16 DOI: 10.1016/j.dark.2026.102226

Agripino Sousa-Neto , Maria Aldinêz Dantas , Javier E. González , Joel C. Carvalho , Jailson Alcaniz

The Universe consists of a variety of objects that formed at different epochs, leading to variations in the formation time which represents the time elapsed from the onset of structure formation until the formation of a particular object. In this work, we present two approaches to reconstruct and constrain the galaxy formation time t_f(z) using non-parametric reconstruction methods, such as Gaussian Processes (GP) and High-performance Symbolic Regression (SR). Our analysis uses age estimates of 32 old passive galaxies and the Pantheon+ type Ia supernova sample, and considers two different values of the Hubble constant H₀ from the SH0ES and Planck Collaborations. When adopting the ΛCDM model and the GP reconstructions, A direct comparison of the reconstructions shows that the GP-based implementations are mutually consistent across the redshift range considered. The SR reconstructions also show good agreement with the GP results and exhibit a compatible redshift evolution of t_f(z), with full agreement at intermediate and high redshifts and only a mild deviation at very low redshifts. The results also show significant differences in the formation time from SH0ES and Planck values, highlighting the impact of the H₀ tension on the cosmological estimates of t_f(z). Overall, this study suggests that galaxies have different evolutionary timescales and that t_f is not constant, with noticeable variations at lower redshifts (z ≲ 0.5).

宇宙由不同时期形成的各种物体组成，导致形成时间的变化，这代表了从结构形成开始到特定物体形成所经过的时间。在这项工作中，我们提出了两种方法来重建和约束星系形成时间tf(z)使用非参数重建方法，如高斯过程（GP）和高性能符号回归（SR）。我们的分析使用了32个古老被动星系和万神殿+ Ia型超新星样本的年龄估计，并考虑了来自SH0ES和普朗克合作组织的哈勃常数H0的两个不同值。当采用ΛCDM模型和GP重建时，直接比较重建结果表明，基于GP的实现在考虑的红移范围内是相互一致的。SR重建也显示出与GP结果的良好一致性，并显示出tf(z)的相容红移演化，在中高红移处完全一致，在非常低的红移处只有轻微的偏差。结果还显示了SH0ES和普朗克值在形成时间上的显著差异，突出了H0张力对tf(z)的宇宙学估计的影响。总的来说，这项研究表明，星系具有不同的演化时间尺度，并且tf不是恒定的，在较低的红移（z > 0.5）处有明显的变化。

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引用次数: 0

Impact of a complex scalar spectator field on baryon asymmetry within spontaneous baryogenesis 复杂标量旁观者场对自发重子发生过程中重子不对称性的影响

IF 6.4 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

Physics of the Dark Universe

Pub Date : 2026-02-01 Epub Date: 2025-12-02 DOI: 10.1016/j.dark.2025.102187

Mattia Dubbini , Orlando Luongo , Marco Muccino

We extend the framework of spontaneous baryogenesis by investigating the generation of baryon asymmetry when the inflaton, θ, is minimally coupled with a complex spectator scalar field ϕ, as θ²|ϕ|². We also consider ϕ non-minimally coupled with the Ricci scalar curvature R, since in previous works a Yukawa-like interaction with gravity has already been shown to provide a significant contribution to the production of baryon asymmetry. We do not consider further interactions of the spectator field with the fermions of the Standard Model, considering it de facto as a dark scalar field. In evaluating the violation of the baryon-number conservation during the reheating epoch, in a perfectly homogeneous and isotropic universe, we follow a semiclassical approach, where θ, ϕ and gravity are considered as classical fields, whereas the fermions are quantized. We solve the equations of motion for the inflaton and spectator fields, respectively at first and zero-order in perturbation theory, neglecting at first stage the expansion of the universe. Afterwards, we quantify how the spectator field modifies the inflationary dynamics and thus find the baryon asymmetry produced via the inflaton decays into fermion-antifermion pairs by computing the corresponding decay amplitudes. In particular, the coupling term θ²|ϕ|² acts as an additional contribution to the square effective mass of the inflaton, increasing its decay amplitudes into fermion-antifermion pairs. Consequently, we expect this to affect the production of the net baryon asymmetry. We therefore obtain small first order correction to standard spontaneous baryogenesis and finally discuss the mass-mixing between fermions. Accordingly, the effects of considering the universe expansion are accounted, showing when the coupling between ϕ and R becomes noticeable in altering the overall baryon asymmetry.

我们扩展了自发重子发生的框架，研究了当膨胀子θ与复杂的旁观者标量场φ最小耦合时重子不对称的产生，为θ2| φ |2。我们还考虑了φ与里奇标量曲率R的非最小耦合，因为在以前的工作中，与重力的类yukawa相互作用已经被证明对重子不对称的产生有重大贡献。我们不考虑观众场与标准模型中的费米子的进一步相互作用，认为它实际上是一个暗标量场。在评估再加热时期重子数守恒的违反时，在一个完全均匀和各向同性的宇宙中，我们遵循半经典方法，其中θ， ϕ和引力被认为是经典场，而费米子是量子化的。我们在微扰理论中分别求解了一阶和零阶膨胀场和观众场的运动方程，在第一阶段忽略了宇宙的膨胀。之后，我们量化了观众场如何改变暴胀动力学，从而通过计算相应的衰减幅度，发现暴胀衰变为费米子-反费米子对所产生的重子不对称性。特别是，耦合项θ2| φ |2对暴胀子的平方有效质量起到了额外的作用，增加了它在费米子-反费米子对中的衰减幅度。因此，我们预计这将影响净重子不对称性的产生。因此，我们得到了标准自发重子发生的小一级修正，最后讨论了费米子之间的质量混合。因此，考虑宇宙膨胀的影响被考虑在内，表明当ϕ和R之间的耦合在改变整体重子不对称性时变得明显。

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引用次数: 0

Power spectrum emulators from neural networks and tree-based methods 来自神经网络和基于树的方法的功率谱仿真器

IF 6.4 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

Physics of the Dark Universe

Pub Date : 2026-02-01 Epub Date: 2025-12-02 DOI: 10.1016/j.dark.2025.102186

Andrei Lazanu

We use two subsets of 2000 and 1000 Quijote simulations to build two power spectrum emulators, allowing for fast computations of the non-linear matter power spectrum. The first emulator is built in terms of seven cosmological parameters: the matter and baryon fraction of the energy density of the Universe Ω_m and Ω_b, the reduced Hubble constant h, the scalar spectral index n_s, the amplitude of matter density fluctuations σ₈, the total neutrino mass M_ν and the dark energy equation of state parameter w, on scales

k \in [0.015, 1.8] h / M p c^{- 1}

. The power spectra can be directly determined at redshifts 0, 0.5, 1, 2 and 3, while for intermediate redshifts these can be interpolated. The second emulator is based on five cosmological parameters, Ω_m, h, n_s, σ₈ and the amplitude of equilateral non-Gaussianity

f_{N L}^{e q}

, at redshifts 0, 0.503, 0.733, 0.997 for

k \in [0.015, 1.8] h / M p c^{- 1}

. The emulators are built on machine learning techniques. In both cases we have investigated both neural networks and tree-based methods and we have shown that the best accuracy is obtained for a neural network with two hidden layers. Both emulators achieve a root-mean-squared relative error of less then 5 % for all the redshifts considered on the scales discussed.

我们使用2000和1000 Quijote模拟的两个子集来构建两个功率谱模拟器，允许快速计算非线性物质功率谱。在k∈[0.015,1.8]h/Mpc−1的尺度下，根据宇宙能量密度的物质和重子分数Ωm和Ωb、约简哈勃常数h、标量谱指数ns、物质密度波动幅度σ8、中微子总质量Mν和暗能量状态方程w这7个宇宙学参数构建了第一个仿真器。功率谱可以在红移0、0.5、1、2和3处直接确定，而对于中间红移，这些可以插值。第二个仿真器基于5个宇宙学参数Ωm、h、ns、σ8以及k∈[0.015,1.8]h/Mpc−1时红移0、0.503、0.733、0.997时等边非高斯性fNLeq的振幅。仿真器建立在机器学习技术的基础上。在这两种情况下，我们都研究了神经网络和基于树的方法，并且我们已经表明，具有两个隐藏层的神经网络获得了最好的精度。两个仿真器在讨论的尺度上考虑的所有红移都实现了小于5%的均方根相对误差。

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引用次数: 0

Phase structure, thermal fluctuations and emission spectrum of nonlinear electrodynamics AdS black holes surrounded by cloud of strings 弦云包围下非线性电动力学AdS黑洞的相结构、热波动和发射光谱

IF 6.4 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

Physics of the Dark Universe

Pub Date : 2026-02-01 Epub Date: 2026-01-03 DOI: 10.1016/j.dark.2025.102207

Faisal Javed , A. Eid , Abdelmalek Bouzenada , Arfa Waseem , N. Mustapha , Munisbek Akhmedov , Yunus Turaev , Ertan Güdekli

This paper presents a comprehensive analysis of the Joule–Thomson (J-T) expansion and thermodynamic properties of charged AdS black holes (BHs) coupled to nonlinear electrodynamics and embedded within a string cloud with particular emphasis on elucidating the profound role of thermal fluctuations. By formulating the equation of state and analyzing the J-T coefficient, we distinguish the heating and cooling phases of the BH and demonstrate how the mass, string cloud parameter and deviation parameter κ influence the transition between them. The isenthalpic curves in the

T - P

plane reveal that larger BH masses enhance cooling efficiency while nonlinear electrodynamics suppresses it. Incorporating logarithmic corrections due to thermal fluctuations, we study the corrected entropy and various thermodynamic potentials, including the Helmholtz free energy, internal energy, enthalpy, Gibbs free energy and heat capacity. Evidence from the analysis suggests that quantum thermal corrections significantly alter the stability profile of AdS BHs. Configurations of small horizon radius exhibit negative heat capacity, thereby entering an unstable regime, whereas sufficiently large BHs undergo a transition to positive capacity, restoring stability and equilibrium. The radiative spectrum, moreover, is characterized by a pronounced peak at intermediate frequencies, echoing the profile of Hawking emission yet distinctly modified through nonlinear electrodynamic contributions. Collectively, these insights establish that nonlinear electrodynamics, the presence of a string cloud, and quantum fluctuations are fundamental determinants in shaping the phase structure, equilibrium properties, and radiative dynamics of AdS BHs.

本文综合分析了非线性电动力学耦合的带电AdS黑洞（BHs）的焦耳-汤姆逊（J-T）膨胀和热力学性质，特别强调了热波动的深刻作用。通过建立状态方程和分析J-T系数，我们区分了黑洞的加热阶段和冷却阶段，并论证了质量、弦云参数和偏差参数κ如何影响它们之间的转变。T - P平面的等焓曲线表明，较大的黑洞质量提高了冷却效率，而非线性电动力学则抑制了冷却效率。结合热波动的对数修正，我们研究了修正后的熵和各种热力学势，包括亥姆霍兹自由能、内能、焓、吉布斯自由能和热容。来自分析的证据表明，量子热修正显著地改变了AdS黑洞的稳定性。视界半径小的构型表现为负热容量，从而进入不稳定状态，而足够大的黑洞经历向正热容量的过渡，恢复稳定和平衡。此外，辐射谱的特点是在中频处有一个明显的峰值，这与霍金发射的轮廓相呼应，但由于非线性电动力贡献而明显改变。总的来说，这些见解确立了非线性电动力学、弦云的存在和量子涨落是形成AdS黑洞的相结构、平衡特性和辐射动力学的基本决定因素。

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引用次数: 0

Interior structure and physical features of dark energy relativistic stars in power law gravity model 幂律引力模型中暗能量相对论恒星的内部结构和物理特征

IF 6.4 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

Physics of the Dark Universe

Pub Date : 2026-02-01 Epub Date: 2025-12-25 DOI: 10.1016/j.dark.2025.102198

M.R. Shahzad , Wajiha Habib , Asifa Ashraf , Muneerah Alomar , Awatef Abidi , Maryam Al Huwayz

The modeling of astrophysical compact objects has recently attracted significant interest of the research community to understand their stable internal structures. In particular, the addition of dark energy as another source of matter configuration in the interiors of such stars has elevated the focus on their theoretical development. In this study, we present a ne model of static, spherically symmetric, and anisotropic compact stars within the framework of f(R) modified theories. The stellar structure is described by a two-fluid system consisting of ordinary matter and dark energy. We develop the analytical solutions to the governing modified field equations using the well-known Finch-Skea ansatz for the metric potentials, coupled with a linear equation of state for the dark energy component. The model parameters, including the metric ansatz, are determined via smooth matching conditions at the boundary between the interior and exterior spacetime regions. To demonstrate the physical viability of the model, we apply our formulation to the compact star 4U 1538-52, utilizing the stable and widely studied

f (R) = R + 2 χ R^{2}

gravity model. We analyze an extensive investigation of the physical features, including the behavior of metric equations, matter variables, energy conditions, and stability criteria. In addition, we evaluate the evolution of the mass function, surface redshift, and compactness factor of the considered compact star candidates. The results confirm the stability, feasibility, and physical impact of the constructed solutions along with presenting additional insight into the interplay between dark energy structures and modified gravity within astrophysical circumstances. Graphical representations of key parameters enhance the clarity of our findings. The results demonstrate that our model is physically acceptable and stable in f(R) gravity.

天体物理致密物体的建模最近引起了研究界的极大兴趣，以了解它们稳定的内部结构。特别是，暗能量作为这类恒星内部物质结构的另一个来源的增加，提高了对它们理论发展的关注。在这项研究中，我们提出了一个在f(R)修正理论框架内的静态、球对称和各向异性致密恒星的新模型。恒星结构被描述为由普通物质和暗能量组成的双流体系统。我们利用著名的芬奇-斯基方差分析得到了控制修正场方程的解析解，并结合了暗能量分量的线性状态方程。模型参数，包括度量参数，通过内外时空区域边界的平滑匹配条件确定。为了证明该模型的物理可行性，我们利用稳定且广泛研究的f(R)=R+2χR2重力模型，将我们的公式应用于紧凑恒星4U 1538-52。我们分析了物理特征的广泛调查，包括度量方程的行为，物质变量，能量条件和稳定性标准。此外，我们评估了被考虑的紧致恒星候选者的质量函数、表面红移和紧致系数的演变。结果证实了构建的解决方案的稳定性、可行性和物理影响，同时对暗能量结构和天体物理环境下修正引力之间的相互作用提供了额外的见解。关键参数的图形表示增强了我们研究结果的清晰度。结果表明，该模型在f(R)重力下是物理上可接受的和稳定的。

{"title":"Interior structure and physical features of dark energy relativistic stars in power law gravity model","authors":"M.R. Shahzad , Wajiha Habib , Asifa Ashraf , Muneerah Alomar , Awatef Abidi , Maryam Al Huwayz","doi":"10.1016/j.dark.2025.102198","DOIUrl":"10.1016/j.dark.2025.102198","url":null,"abstract":"<div><div>The modeling of astrophysical compact objects has recently attracted significant interest of the research community to understand their stable internal structures. In particular, the addition of dark energy as another source of matter configuration in the interiors of such stars has elevated the focus on their theoretical development. In this study, we present a ne model of static, spherically symmetric, and anisotropic compact stars within the framework of <em>f</em>(<em>R</em>) modified theories. The stellar structure is described by a two-fluid system consisting of ordinary matter and dark energy. We develop the analytical solutions to the governing modified field equations using the well-known Finch-Skea ansatz for the metric potentials, coupled with a linear equation of state for the dark energy component. The model parameters, including the metric ansatz, are determined via smooth matching conditions at the boundary between the interior and exterior spacetime regions. To demonstrate the physical viability of the model, we apply our formulation to the compact star 4U 1538-52, utilizing the stable and widely studied <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>R</mi><mo>)</mo></mrow><mo>=</mo><mi>R</mi><mo>+</mo><mn>2</mn><mi>χ</mi><msup><mi>R</mi><mn>2</mn></msup></mrow></math></span> gravity model. We analyze an extensive investigation of the physical features, including the behavior of metric equations, matter variables, energy conditions, and stability criteria. In addition, we evaluate the evolution of the mass function, surface redshift, and compactness factor of the considered compact star candidates. The results confirm the stability, feasibility, and physical impact of the constructed solutions along with presenting additional insight into the interplay between dark energy structures and modified gravity within astrophysical circumstances. Graphical representations of key parameters enhance the clarity of our findings. The results demonstrate that our model is physically acceptable and stable in <em>f</em>(<em>R</em>) gravity.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"51 ","pages":"Article 102198"},"PeriodicalIF":6.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145977319","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}

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