Physics of the Dark Universe最新文献

Data-driven modeling of rotation curves with artificial neural networks 基于人工神经网络的旋转曲线数据驱动建模

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

Physics of the Dark Universe

Pub Date : 2026-02-03 DOI: 10.1016/j.dark.2026.102240

Gabriela Garcia-Arroyo , Isidro Gómez-Vargas , J. Alberto Vázquez

Galactic rotation curves are crucial for understanding the distribution of mass in galaxies. Despite advances in precision observations, there are discrepancies between the inferred mass from luminosity and the observed rotational velocities, often attributed to dark matter. While traditional parametric models provide valuable insights, they struggle with complex galactic features like prominent bulges and non-circular motions. In this study, we apply artificial neural networks to generate robust, data-driven models, tailored to each galaxy, for the rotation curves of spiral galaxies using high-quality observational data. Our approach demonstrates that neural networks can effectively capture the intricate structure of rotation curves without relying on predefined astrophysical assumptions. By comparing the data-based models with the Navarro-Frenk-White model under two different assumptions for the stellar component, we classify galaxies based on the model that best fits their rotation curves, offering insights into the limitations and strengths of both theoretical and data-based methods. This work highlights the potential of machine learning techniques in identifying galaxies whose dynamics are not well captured by standard theoretical models, pointing to the need for more refined physical descriptions.

星系旋转曲线对于理解星系的质量分布是至关重要的。尽管精密观测取得了进步，但从光度推断出的质量与观测到的旋转速度之间存在差异，这通常归因于暗物质。虽然传统的参数模型提供了有价值的见解，但它们难以处理复杂的星系特征，如突出的凸起和非圆运动。在这项研究中，我们利用高质量的观测数据，应用人工神经网络为每个星系量身定制了鲁棒的数据驱动模型，用于螺旋星系的旋转曲线。我们的方法表明，神经网络可以有效地捕获旋转曲线的复杂结构，而不依赖于预定义的天体物理假设。通过比较基于数据的模型和纳瓦罗-弗兰克-怀特模型在两种不同假设下的恒星成分，我们根据最适合其旋转曲线的模型对星系进行分类，从而深入了解理论和基于数据的方法的局限性和优势。这项工作强调了机器学习技术在识别那些动力学不能被标准理论模型很好地捕获的星系方面的潜力，指出需要更精细的物理描述。

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引用次数: 0

WIMP freeze-out dynamics under Tsallis statistics 在Tsallis统计下的WIMP冻结动力学

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

Physics of the Dark Universe

Pub Date : 2026-02-02 DOI: 10.1016/j.dark.2026.102241

Matias P. Gonzalez, Roberto A. Lineros

We generalize thermal WIMP (Weakly Interacting Massive Particle) freeze-out within Tsallis nonextensive statistics. Using Curado–Tsallis q-distributions f_q(E; μ, T) we compute q-deformed number and energy densities, pressure, entropy density and Hubble rate, {n_q, ρ_q, P_q, s_q, H_q}. The Boltzmann equation is generalized accordingly to obtain the comoving abundance Y_χ,q(x) and relic density Ω_χ,qh² for a dark-matter candidate χ in a model-independent setup. The thermally averaged cross section is expanded as

{〈 σ v 〉}_{q} \approx a + b {〈 v_{r e l}^{2} 〉}_{q}

up to p-wave. The freeze-out parameter x_f(q) is determined from Γ_ann,q(T_f) ≃ H_q(T_f) using a q-logarithmic inversion, with the expansion rate modified through ultra-relativistic rescalings R_ρ(q) of the effective relativistic degrees of freedom g_* and g_*s. We show that x_f increases with q and that QCD-threshold features propagate into Y_χ,q(x) and Ω_χ,qh². We then perform two q-grid scans: fixing ⟨σv⟩_q while varying the dark-matter mass m_χ, and fixing m_χ while varying the s-wave coefficient a. For an s-wave dominated scenario we construct χ² profiles in these planes by comparing Ω_χ,qh² with the Planck benchmark

Ω_{c} h^{2} = 0.120 \pm 0.001

. In both cases we find a clear degeneracy in the preferred nonextensive parameter q_best along valleys in parameter space. However, fixed-mass scans (varying ⟨σv⟩_q) are significantly more constraining than fixed-cross-section scans, reflecting that Ω_χ,qh² is mainly controlled by ⟨σv⟩_q, so that for realistic cross sections the best-fit q_best remains close to the extensive limit q → 1.

我们将热WIMP（弱相互作用大质量粒子）冻结推广到Tsallis的非扩展统计中。利用Curado-Tsallis q分布fq（E; μ， T）计算q变形数和能量密度、压力、熵密度和哈勃率{nq， ρq, Pq, sq, Hq}。对玻尔兹曼方程进行了相应的推广，得到了在模型无关设置下暗物质候选物质χ的运动丰富度Yχ，q(x)和遗迹密度Ωχ，qh2。热平均截面扩展为< σv > q≈a+b < vrel2 > q，直至p波。通过对有效相对论自由度g*和g*s的超相对论重标Rρ(q)来修正膨胀率，利用q-对数反演从Γann，q（Tf） ≃ Hq（Tf）处确定冻结参数xf(q)。我们证明xf随q增加，qcd -阈值特征传播到Yχ，q(x)和Ωχ，qh2。然后我们执行两个q网格扫描：在改变暗物质质量mχ的同时固定⟨σv⟩q，并在改变s波系数a的同时固定mχ。对于s波主导的场景，我们通过将Ωχ，qh2与普朗克基准Ωch2=0.120±0.001进行比较，在这些平面中构建χ2剖面。在这两种情况下，我们发现优选的非扩展参数qbest在参数空间中沿谷具有明显的简并性。然而，固定质量扫描（改变⟨σv⟩q）明显比固定截面扫描更具约束，反映了Ωχ，qh2主要由⟨σv⟩q控制，因此对于实际横截面，最佳拟合qbest仍然接近扩展极限q → 1。

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引用次数: 0

Violation of Bell inequality from a squeezed coherent state of inflationary perturbations 膨胀扰动的压缩相干态对贝尔不等式的破坏

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 DOI: 10.1016/j.dark.2026.102218

Aurindam Mondal , Rathul Nath Raveendran

We investigate the quantum nature of primordial perturbations by studying the violation of Bell inequality when the initial state is taken to be a coherent state rather than the usual Bunch-Davies vacuum. As inflation progresses, the coherent state evolves into a squeezed coherent state, and we derive an analytical expression for the expectation value of the Bell operator constructed from pseudo-spin operators. Our analysis shows that although the expectation value of the Bell operator initially deviates from the vacuum case, it asymptotically saturates to the same value. Notably, this saturation occurs more rapidly for non-zero coherent state parameters, indicating that a larger one-point correlation function accelerates the approach to maximal Bell inequality violation.

我们通过研究当初始状态被视为相干状态而不是通常的Bunch-Davies真空时贝尔不等式的违反来研究原始扰动的量子性质。随着膨胀的进行，相干态演化为压缩相干态，并导出了由伪自旋算子构造的贝尔算子期望值的解析表达式。我们的分析表明，虽然贝尔算子的期望值最初偏离真空情况，但它渐近饱和到相同的值。值得注意的是，对于非零相干状态参数，这种饱和发生得更快，这表明更大的一点相关函数加速了向最大贝尔不等式违背的接近。

引用次数: 0

Exact and numerical analysis of accretion dynamics with perfect and polytropic fluids around nonlinear charged black holes 非线性带电黑洞周围完美多向流体吸积动力学的精确数值分析

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 DOI: 10.1016/j.dark.2026.102233

Ghulam Fatima , Abdelmalek Bouzenada , Orhan Donmez , Allah Ditta , G. Mustafa , Farruh Atamurotov

In this study, we examine the accretion of perfect and polytropic fluids onto Barrow’s nonlinear charged black hole models, described by a static spherically symmetric spacetime with a metric function X(r) explicitly dependent on the Yang-Mills coupling parameter α, magnetic charge Q, and black hole mass M. We employ two equations of state: (i)

p = ω (ρ - ρ_{0})

, which incorporates a reference density ρ₀ to account for a nonzero rest energy baseline, and (ii)

p = κ ρ

, representing a conventional linear equations of state. Applying the steady-state approximation, we derive the conservation equations for mass, momentum, and energy, which allow analytical determination of the critical (sonic) points and the mass accretion rate. In this case, the analysis reveals that increasing either α or Q reduces the fluid inflow velocity and local sound speed while simultaneously enhancing the accretion rate near the event horizon. Also, both equations of state models exhibit smooth, continuous transitions through the sonic points, and numerical evaluations demonstrate pronounced effects of α and Q on the horizon geometry, location of critical points, fluid density, and sound speed, quantitatively illustrating the influence of nonlinear electrodynamics and Barrow deformation on relativistic accretion dynamics.

在本研究中，我们研究了完美和多元流体在Barrow的非线性带电黑洞模型上的吸积，该模型由静态球对称时空描述，度量函数X(r)显式依赖于Yang-Mills耦合参数α、磁荷Q和黑洞质量m。(i) p=ω(ρ−ρ0)，其中包含一个参考密度ρ0，以说明非零的静止能量基线，（ii） p=κρ，表示传统的线性状态方程。应用稳态近似，我们推导出质量、动量和能量的守恒方程，从而可以解析确定临界（声波）点和质量吸积率。在这种情况下，分析表明，增加α或Q都可以降低流体流入速度和局部声速，同时提高视界附近的吸积速率。此外，两种状态模型的方程都表现出平滑、连续的声波点过渡，数值评估表明α和Q对视界几何、临界点位置、流体密度和声速的显著影响，定量地说明了非线性电动力学和巴罗变形对相对论吸积动力学的影响。

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引用次数: 0

Anisotropic compact stars under quintessence field with vanishing gravitational complexity factor 引力复杂性因子消失的精萃场下各向异性致密恒星

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 DOI: 10.1016/j.dark.2026.102220

S. Khan , Javlon Rayimbaev , Sarvar Iskandarov , Aybek Seytov , Inomjon Ibragimov , Sokhibjan Muminov

This work studies the construction of anisotropic self-gravitating star models influenced by a surrounding quintessence field described by a parameter ω_q with

- 1 < ω_{q} < - \frac{1}{3}

, under the theoretical requirement of a vanishing gravitational complexity factor. The complexity-free constraint, originally proposed as a measure of the structural inhomogeneity and pressure anisotropy of relativistic stellar fluids, is employed to obtain astrophysically relevant solutions of general relativistic field equations. By considering a suitable metric potential, we derive exact expressions for the matter density, principal stresses, and anisotropy factor. The influence of the quintessence field on stellar structure is analyzed in detail, highlighting its role in tuning the pressure anisotropy and energy distribution within the stellar distribution. To ensure realistic stellar modeling, we examine central regularity, positivity of density and principal stresses, energy conditions, causality, and stability requirements. Furthermore, matching conditions with the exterior spacetime are imposed to determine the unknown constants. The resulting stellar configurations are shown to be consistent with observational data of compact stars, thereby demonstrating that the combined effects of the quintessence field and the vanishing complexity condition provide an elegant framework for modeling anisotropic relativistic configuration.

本文研究了在引力复杂性因子消失的理论要求下，由参数ωq用−1<；ωq<；−13描述的周围精场影响的各向异性自引力恒星模型的构建。无复杂性约束最初是作为相对论性恒星流体结构非均匀性和压力各向异性的度量而提出的，用于获得广义相对论场方程的天体物理相关解。通过考虑合适的度量势，我们推导出物质密度、主应力和各向异性因子的精确表达式。详细分析了精萃场对恒星结构的影响，重点介绍了精萃场对恒星内部压力各向异性和能量分布的调节作用。为了确保真实的恒星建模，我们检查了中心规则，密度和主应力的正性，能量条件，因果关系和稳定性要求。此外，通过施加与外部时空的匹配条件来确定未知常数。由此得到的恒星构型与致密恒星的观测数据一致，从而证明了精萃场和消失复杂性条件的联合效应为各向异性相对论构型的建模提供了一个优雅的框架。

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引用次数: 0

Dual impact of matter coupling on LMC X-4 pulsar observations and stability 物质耦合对LMC X-4脉冲星观测和稳定性的双重影响

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 DOI: 10.1016/j.dark.2026.102230

Asifa Ashraf , Tayyab Naseer , Hammad Afzal , Chengxun Yuan , Ozodbek Rahimov , Ahmadjon Abdujabbarov

This study examines the behavior of compact astrophysical objects within a matter-geometry coupled f(R) gravity model. The modified field equations are expressed for a static interior spacetime with an anisotropic matter distribution. Applying two well-defined radial components of the metric ansatz and anisotropic pressures allows for analytical solutions to these equations. In both theoretical models, integrating the differential equations introduces constants, which are fixed using boundary conditions. Furthermore, the condition of null radial pressure at the boundary is used to determine these constants. Additionally, we visually assess certain important features that ensure the physical acceptability of the proposed model and support our analysis with observational data from LMC X-4. Our theoretical research shows that both models meet the physical viability and stability requirements. Further, our investigation also contributes to the knowledge of how the modified gravity model influences the interior structure of compact stars, paving the way for future studies.

本研究在物质-几何耦合f(R)引力模型中考察了紧凑天体物理对象的行为。对具有各向异性物质分布的静态内部时空，给出了修正的场方程。应用两个定义良好的径向分量的度量和各向异性压力允许解析解决这些方程。在这两个理论模型中，积分微分方程引入了常数，这些常数是用边界条件固定的。此外，利用边界处径向压力为零的条件来确定这些常数。此外，我们从视觉上评估了某些重要特征，以确保所提出模型的物理可接受性，并支持我们使用LMC X-4的观测数据进行分析。我们的理论研究表明，这两种模型都满足物理活力和稳定性要求。此外，我们的研究还有助于了解修改后的引力模型如何影响致密恒星的内部结构，为未来的研究铺平道路。

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引用次数: 0

Late-time cosmology in Weyl-type f(Q, T) modified gravity: Analytic background solutions and observational constraints from H(z), Pantheon+, and DESI 修正引力的weyl型f（Q， T）晚时间宇宙学：来自H(z)、Pantheon+和DESI的分析背景解和观测约束

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 DOI: 10.1016/j.dark.2026.102231

Aylin Çalışkan

<div><div>We study the late-time cosmological implications of Weyl-type f(Q, T) modified gravity in a spatially flat FLRW background. Working in Weyl geometry, where non-metricity is sourced by a gauge field wμ, we enforce the vanishing Weyl scalar condition <math><mrow><mover><mi>R</mi><mo>¯</mo></mover><mo>=</mo><mn>0</mn></mrow></math> through a Lagrange multiplier, which yields modified field equations containing both a Proca-like vector contribution and a matter-geometry coupling via f(Q, T). By adopting the linear ansatz <math><mrow><mi>f</mi><mrow><mo>(</mo><mi>Q</mi><mo>,</mo><mi>T</mi><mo>)</mo></mrow><mo>=</mo><mi>α</mi><mi>Q</mi><mo>+</mo><mfrac><mi>β</mi><mrow><mn>6</mn><msup><mi>κ</mi><mn>2</mn></msup></mrow></mfrac><mi>T</mi><mo>+</mo><mi>γ</mi></mrow></math> and a homogeneous Weyl vector <math><mrow><msub><mi>w</mi><mi>μ</mi></msub><mo>=</mo><mrow><mo>(</mo><mi>ψ</mi><mrow><mo>(</mo><mi>t</mi><mo>)</mo></mrow><mo>,</mo><mn>0</mn><mo>,</mo><mn>0</mn><mo>,</mo><mn>0</mn><mo>)</mo></mrow></mrow></math> (so that <math><mrow><mi>Q</mi><mo>=</mo><mn>6</mn><msup><mi>ψ</mi><mn>2</mn></msup></mrow></math>), we derive the generalized Friedmann equations and close the system under the approximation λ ≃ κ2. The Weyl constraint admits the branch <math><mrow><mi>ψ</mi><mo>=</mo><mi>H</mi></mrow></math>, and consistency with the generalized Proca equation selects the massless effective mode <math><mrow><msubsup><mi>m</mi><mrow><mrow><mi>e</mi></mrow><mi>f</mi><mi>f</mi></mrow><mn>2</mn></msubsup><mo>=</mo><mn>0</mn></mrow></math>, fixing α and leaving (β, γ) as the relevant phenomenological parameters. For a dust sector (<math><mrow><mi>p</mi><mo>=</mo><mn>0</mn></mrow></math>), the dynamics reduces to a Riccati-type equation that can be integrated analytically, leading to a closed-form expression for the Hubble function H(z) and well-defined viability conditions (notably <math><mrow><mi>β</mi><mo>≠</mo><mo>−</mo><mn>2</mn></mrow></math> and H2(z) ≥ 0). We then confront the model with current late-time data using an affine-invariant MCMC analysis with cosmic chronometer H(z) measurements, Pantheon+ SNe Ia, and DESI BAO. The combined dataset yields <math><mrow><msub><mi>H</mi><mn>0</mn></msub><mo>=</mo><mn>67.86</mn><mo>±</mo><mn>0.37</mn></mrow></math>, <math><mrow><mi>β</mi><mo>=</mo><mn>0</mn><mo>.</mo><msubsup><mn>27</mn><mrow><mo>−</mo><mn>0.13</mn></mrow><mrow><mo>+</mo><mn>0.11</mn></mrow></msubsup></mrow></math>, and <math><mrow><mi>γ</mi><mo>=</mo><mo>−</mo><mn>1.8</mn><mo>×</mo><msup><mn>10</mn><mn>4</mn></msup><mo>±</mo><mn>1.0</mn></mrow></math>, with a goodness of fit comparable to ΛCDM (<math><mrow><msubsup><mi>χ</mi><mrow

我们研究了空间平坦FLRW背景下weyl型f（Q， T）修正引力的晚时间宇宙学意义。在Weyl几何中，非度量性来源于规范场wμ，我们通过拉格朗日乘子实现消失的Weyl标量条件R¯=0，从而产生修正的场方程，其中包含proca类向量贡献和通过f（Q， T）的物质-几何耦合。采用线性矩阵f(Q，T)=αQ+β6κ2T+γ和齐次Weyl向量wμ=(ψ(T),0,0,0)（使得Q=6ψ2），导出了广义Friedmann方程，并将系统封闭在近似λ ≃ κ2下。Weyl约束允许分支ψ=H，与广义Proca方程的一致性选择无质量有效模态meff2=0，固定α，留下（β, γ）作为相关的现象学参数。对于尘埃扇区（p=0），动力学简化为可以解析积分的riccti型方程，从而得到哈勃函数H(z)的封闭表达式和定义良好的生存条件（特别是β≠−2和H2(z) ≥ 0）。然后，我们利用宇宙天文钟H(z)测量、Pantheon+ SNe Ia和DESI BAO的仿射不变MCMC分析，将当前的晚时间数据与模型进行对比。合并后的数据集得到H0=67.86±0.37,β=0.27−0.13+0.11,γ=−1.8×104±1.0，拟合优度与ΛCDM相当（χ 2=1.122 vs . 1.115）。推断的H0与普朗克推断的值一致，但仍低于局部距离阶梯估计值。最后，我们重建了宇宙学层次{q， j, s, r}，并找到了一个具有渐近de Sitter未来的标准减速-加速过渡，而高阶运动量在1σ - 2σ范围内保持光滑并接近ΛCDM。因此，具有线性（Q， T）扇区的weyl型f（Q， T）引力提供了与当前观测相兼容的分析可处理的晚时间宇宙学，为高阶运动学中的小的，可测试的偏离留下了空间。

引用次数: 0

Search for spatial coincidence between magnetars and IceCube detected neutrinos 寻找磁星和冰立方探测到的中微子之间的空间一致性

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 DOI: 10.1016/j.dark.2026.102234

Fathima Shifa M․ , Shantanu Desai

We implement a search for spatial coincidence between high energy neutrinos detected by the IceCube neutrino detector (using the publicly available 10-year muon track data) and 37 magnetars, including six extragalactic sources. We use the unbinned maximum likelihood method for our analysis. We do not find any such spatial association between any of the known magnetars and IceCube-detected neutrinos. Therefore, we conclude that none of the known galactic or extragalactic magnetars contribute to the diffuse neutrino flux observed in IceCube. A stacked analysis also does not show a statistically significant excess.

我们对冰立方中微子探测器探测到的高能中微子（使用公开可用的10年μ子轨道数据）与37颗磁星（包括6颗河外源）之间的空间一致性进行了搜索。我们使用无箱最大似然法进行分析。我们没有发现任何已知磁星和冰立方探测到的中微子之间存在这样的空间关联。因此，我们得出结论，没有任何已知的星系或星系外磁星对冰立方观测到的弥散中微子通量有贡献。堆叠分析也没有显示统计上显著的过剩。

引用次数: 0

Predictive one-zero with vanishing sub-trace texture in neutrino mass matrix in light of dark matter and neutrinoless double beta decay 基于暗物质和无中微子双β衰变的中微子质量矩阵中消失子迹织体的预测1 - 0

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 DOI: 10.1016/j.dark.2026.102228

Ankush Choudhary , Sangeeta Dey , Rishu Verma , Manoj Kumar , B.C. Chauhan , Mahadev Patgiri

In this work, we investigate a predictive class of neutrino mass matrices characterized by one texture zero and one vanishing sub-trace within the framework of the scotogenic model, wherein neutrino masses, dark matter, and neutrinoless double beta decay are intrinsically correlated. We analyze twelve viable texture structures—namely B_1,4,5,

C_{1, 2, \dots, 5}

, D_4,5, and F_5,6—and examine their implications for the effective Majorana mass (|M_ee|) governing neutrinoless double beta decay (0νββ). Remarkably, all non-zero entries of the neutrino mass matrix can be parametrized in terms of this effective Majorana mass, establishing a direct theoretical link between low-energy observables and high-scale parameters of the model. Among the twelve textures, eleven predict dark matter masses of order TeV and yield correlated bounds on |M_ee|—making them testable in current and forthcoming 0νββ experiments—while the textures D₄ and F_5,6 exhibit comparatively weaker correlations. In contrast, the texture C₅ is excluded due to its requirement of unrealistically large Yukawa couplings and its inability to realize dark matter in the TeV regime. Our analysis thus identifies a subset of predictive neutrino mass textures that consistently relate dark matter phenomenology and neutrinoless double beta decay observables within the scotogenic paradigm.

在这项工作中，我们研究了在scotogenic模型框架内具有一个纹理零和一个消失子迹特征的预测类中微子质量矩阵，其中中微子质量，暗物质和无中微子双β衰变具有内在相关性。我们分析了12种可行的织构结构，即B1、4、5、C1、2、…、5、D4、5和F5、6，并研究了它们对控制中微子双β衰变（0νββ）的有效马约拉纳质量（|Mee|）的影响。值得注意的是，中微子质量矩阵的所有非零项都可以用有效马约拉纳质量进行参数化，从而在低能观测值和模型的高尺度参数之间建立了直接的理论联系。在12个织构中，有11个织构预测了TeV阶的暗物质质量，并在|Mee|上产生了相关界限，这使得它们可以在当前和即将到来的0νββ实验中进行测试，而D4和f5,6表现出相对较弱的相关性。相比之下，结构C5被排除在外，因为它需要不切实际的大汤川耦合，并且无法在TeV域中实现暗物质。因此，我们的分析确定了一个预测中微子质量结构的子集，这些结构始终将暗物质现象学和可观测到的无中微子双β衰变联系在一起。

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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 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