Annals of Physics最新文献

英文中文

Magnetic domain walls in Ferromagnetic Spin-2 Bose–Einstein condensates 铁磁自旋-2玻色-爱因斯坦凝聚体的磁畴壁

IF 3 3区物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY

Annals of Physics

Pub Date : 2025-10-01 DOI: 10.1016/j.aop.2025.170241

Hao Zhu , Su-Ye Lü , Xiao-Yang Shi , Wu-Ming Liu

We report the formation of magnetic domain wall (MDW) in ferromagnetic spin-2 Bose–Einstein condensates, triggered by Raman-type spin–orbit coupling (SOC). In this study, we explore the generation and deformation of the MDW basing on both mean-field theory and hydrodynamic theory. The MDW cannot be formed by bare SOC, while emerges when rotation effect is considered. A typical kink shaped longitude magnetization and bell shaped transverse magnetization of the MDW are proposed, and the superfluid velocity field calculations indicates the MDW is topological nontrivial. The evolution of MDW with SOC is systematic studied through degree of phase separation, topological charge, and particle number transformation. Moreover, a first-order phase transition happens when rotation frequency exceeds a critical value, and novel wall–vortex complexes appear. The stability of the MDW is also discussed through real-time dynamics in the presence of Gaussian noise that MDW can survive for a long period of time with strong SOC. Our work paves the way to explore exotic topological excitations in high-spin system.

本文报道了由拉曼型自旋-轨道耦合（SOC）引发的铁磁自旋-2玻色-爱因斯坦凝聚体中磁畴壁（MDW）的形成。本文从平均场理论和水动力理论两方面探讨了波浪的产生和变形。单片有机硅不能形成单片有机硅，在考虑旋转效应的情况下才会形成单片有机硅。提出了一种典型的扭结型经度磁化和钟形横向磁化，超流速度场计算表明，MDW具有拓扑非平凡性。从相分离度、拓扑电荷和粒子数变换等方面系统地研究了含荷电硅纳米管的演化过程。当旋转频率超过临界值时，会发生一阶相变，出现新的壁涡复合物。通过实时动力学分析，讨论了在高斯噪声存在的情况下MDW的稳定性，表明MDW可以在较强的SOC下长时间存活。我们的工作为探索高自旋系统中的奇异拓扑激发铺平了道路。

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引用次数: 0

Quantum phases in a Bose–Einstein condensate loaded in two crossed high-finesse optical cavities with orthogonal polarizations 在两个正交偏振的交叉高精细光学腔中加载玻色-爱因斯坦凝聚体中的量子相

IF 3 3区物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY

Annals of Physics

Pub Date : 2025-10-01 DOI: 10.1016/j.aop.2025.170237

Zhao-Di Wu, Wei Qin, Dong-Chen Zheng, Yuan-Hong Chen, Renyuan Liao

We consider a Bose–Einstein condensate (BEC) coupled to two crossed optical cavities with orthogonal polarization modes via the scalar and vectorial polarizabilities of the atoms. We determine the ground-state phase diagram and investigate the behaviors of superradiant order parameters and the photon numbers in both cavities under various conditions. With the set parameters, we find that the system accommodates three distinct phases: a normal phase with no photons in both cavities (

NP

), a superradiant phase with photons only in cavity 1 (

{SR}_{1}

) and a superradiant phase with photons in both cavities (

{SR}_{12}

). We explore the effects of the coupling angle on the phase boundaries under different magnitudes of cavity detuning in the two cavities. We find that the coupling angle strongly modifies the boundary between

{SR}_{1}

and

{SR}_{12}

. In particular, when the coupling angle is equal to

90 °

, the phase of

{SR}_{12}

is completely suppressed.

我们考虑了一个玻色-爱因斯坦凝聚体（BEC）通过原子的标量极化率和矢量极化率耦合到两个具有正交极化模式的交叉光学腔。我们确定了基态相图，并研究了不同条件下两个腔内超辐射阶参量和光子数的行为。在设定的参数下，我们发现系统可以容纳三个不同的相位：两个腔中没有光子的正常相位（NP），只有光子在腔1中的超辐射相位（SR1）和两个腔中都有光子的超辐射相位（SR12）。研究了两腔在不同失谐幅度下耦合角对相界的影响。我们发现耦合角强烈地改变了SR1和SR12之间的边界。特别是当耦合角为90°时，SR12的相位被完全抑制。

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引用次数: 0

Accelerating FJNW metric 加速FJNW度量

IF 3 3区物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY

Annals of Physics

Pub Date : 2025-09-29 DOI: 10.1016/j.aop.2025.170239

Homayon Anjomshoa, Behrouz Mirza, Alireza Azizallahi

We derive exact form of accelerating Fisher-Janis-Newman-Winicour (FJNW) metric by a simple perturbative method. We also argue that by using Buchdahl transformations one can obtain the same accelerating FJNW metric. We investigate singularities of the accelerating FJNW metric and study their effects on global and local structures of this spacetime. We also study geodesics and stability of circular orbits.

用一种简单的微扰方法导出了加速Fisher-Janis-Newman-Winicour （FJNW）度量的精确形式。我们还认为，通过使用Buchdahl变换，可以获得相同的加速FJNW度量。我们研究了加速FJNW度量的奇异性，并研究了它们对该时空的全局和局部结构的影响。我们还研究了圆轨道的测地线和稳定性。

引用次数: 0

Gravitational weak lensing and shadow radius of black holes in Horndeski gravity: Effects of plasma and scalar modifications Horndeski引力中黑洞的引力弱透镜效应和阴影半径：等离子体和标量修正的影响

IF 3 3区物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY

Annals of Physics

Pub Date : 2025-09-25 DOI: 10.1016/j.aop.2025.170209

Husanboy Hoshimov , Shakhzod Orzuev , Farruh Atamurotov , Ahmadjon Abdujabbarov

In this study, we investigate the impact of Horndeski gravity on the shadow radius and weak gravitational lensing around black holes, with particular focus on how plasma environments influence these phenomena. By considering various plasma distributions, including homogeneous and inhomogeneous models, we examine how gravitational lensing deviates from the vacuum case due to both gravitational effects and plasma-induced inhomogeneities. We find that these deviations can be observed in hot gas environments, such as those within galaxy clusters. Using the photon orbit equations in Horndeski spacetime, we analyze the black hole shadow and weak lensing phenomena. By comparing our theoretical predictions to observational data from the Event Horizon Telescope (EHT) for Sagittarius A*, we constrain key parameters of Horndeski gravity. Additionally, we explore the magnification and positioning of lensed images, and provide detailed calculations of the weak deflection angle and magnification for sources near different galaxies, connecting theoretical models with empirical observations.

在这项研究中，我们研究了霍恩德斯基引力对黑洞周围阴影半径和弱引力透镜的影响，特别关注等离子体环境如何影响这些现象。通过考虑各种等离子体分布，包括均匀和非均匀模型，我们研究了引力透镜如何由于引力效应和等离子体诱导的不均匀性而偏离真空情况。我们发现这些偏差可以在热气体环境中观察到，比如在星系团中。利用霍恩德斯基时空中的光子轨道方程，分析了黑洞阴影和弱透镜现象。通过将我们的理论预测与事件视界望远镜（EHT）对人马座A*的观测数据进行比较，我们约束了Horndeski引力的关键参数。此外，我们还探讨了透镜图像的放大倍率和定位，并提供了不同星系附近光源的弱偏转角和放大倍率的详细计算，将理论模型与经验观测联系起来。

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引用次数: 0

Dynamics of warm inflation in Rastall gravity 拉斯托引力中的热暴胀动力学

IF 3 3区物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY

Annals of Physics

Pub Date : 2025-09-23 DOI: 10.1016/j.aop.2025.170232

Ines G. Salako , Isaac M. Vitohekpon , Ferdinan Mavoa , V.A. Monwanou

Within the strong dissipation regime, our study delves into warm inflation set against the backdrop of Rastall gravity. By employing a scalar field in a FLRW universe, we obtained modified field equations. Subsequently, using slow-roll approximations, we deduced the slow-roll parameters and then determined the power spectra for both scalar and tensor perturbations along with their associated spectral indices. We examined both Chaotic and Natural potentials, estimating the scalar spectral index and tensor-to-scalar ratio for scenarios with constant as well as variable dissipation factor

Γ

. Our results indicate that potentials previously dismissed may be revived within the framework of Rastall gravity by appropriately selecting the Rastall parameter

λ_{Ras}

. Furthermore, it is evident that, within the warm inflationary context, both potentials comply with the Planck 2018 constraints at Planckian and sub Planckian energy scales.

在强耗散状态下，我们的研究深入研究了以拉斯塔尔引力为背景的热暴胀。通过在FLRW宇宙中引入标量场，我们得到了修正的场方程。随后，使用慢滚近似，我们推导了慢滚参数，然后确定了标量和张量摄动的功率谱及其相关的谱指数。我们检查了混沌势和自然势，估计了恒定和可变耗散因子Γ情况下的标量谱指数和张量-标量比。我们的研究结果表明，在Rastall重力框架内，通过适当选择Rastall参数λRas，可以使先前被忽略的势恢复。此外，很明显，在温暖的暴胀背景下，这两种势都符合普朗克2018在普朗克和亚普朗克能量尺度上的约束。

引用次数: 0

Long-lived quasinormal modes of brane-localized Reissner–Nordström–de Sitter black holes 膜定域Reissner-Nordström-de Sitter黑洞的长寿命准正态模式

IF 3 3区物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY

Annals of Physics

Pub Date : 2025-09-23 DOI: 10.1016/j.aop.2025.170238

Zainab Malik

We study the quasinormal modes of a massive scalar field propagating on the Reissner–Nordström–de Sitter (RNdS) black hole background on a 3+1-dimensional brane embedded in a higher-dimensional world. Using the WKB method supplemented with Padé approximants and validated by time-domain integration via the Prony method, we compute the dominant quasinormal frequencies for a wide range of black hole and field parameters. We show that the presence of the cosmological constant, black hole charge, and bulk dimensionality significantly affect the oscillation frequencies and damping rates of the scalar perturbations. In particular, we observe the emergence of long lived modes and slowly decaying oscillatory tails in the regime of large field mass. The results demonstrate good agreement between the frequency- and time-domain methods, reinforcing the reliability of the semi-analytic approach in this context.

本文研究了嵌入高维世界的3+1维膜上在Reissner-Nordström-de Sitter （RNdS）黑洞背景上传播的大质量标量场的拟正态模。利用WKB方法补充pad近似，并通过proony方法进行时域积分验证，我们计算了大范围黑洞和场参数的主导拟正态频率。我们发现宇宙常数、黑洞电荷和体维的存在显著影响标量扰动的振荡频率和阻尼率。特别是，我们观察到在大场质量下出现了长寿命模式和缓慢衰减的振荡尾。结果表明，频域方法和时域方法之间具有良好的一致性，增强了半解析方法在这种情况下的可靠性。

引用次数: 0

Second-order approximation of Nojiri–Odintsov infrared cutoff through heuristic expansion: A refined framework for holographic dark energy dynamics with Ricci–Gauss–Bonnet form 通过启发式展开Nojiri-Odintsov红外截止的二阶逼近：Ricci-Gauss-Bonnet形式全息暗能量动力学的一个改进框架

IF 3 3区物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY

Annals of Physics

Pub Date : 2025-09-22 DOI: 10.1016/j.aop.2025.170220

Aziza Altaibayeva , Assem Assetkhan , Surajit Chattopadhyay

This work presents a unified treatment of Nojiri–Odintsov holographic dark energy, encompassing its Ricci–Gauss–Bonnet realization and a second-order approximation as a particular case of the generalized framework. By incorporating higher-order curvature corrections from the Gauss–Bonnet invariant and the Ricci scalar, we construct an extended HDE model and study the evolution of the equation-of-state parameter in both interacting and non-interacting scenarios. The analysis reveals possible quintessence-to-phantom transitions, with observational validation from cosmic chronometer and Planck 2018 datasets. The outcomes indicate the role of higher-curvature corrections provide a viable description of late-time cosmic acceleration. Finally, within the Ricci–Gauss–Bonnet and Nojiri–Odintsov holographic frameworks, we find that the reconstructed

w_{tot} (z)

exhibits the DESI-preferred quintessence–phantom crossing, although the Hubble tension between Planck and SH0ES determinations of

H_{0}

remains unresolved.

这项工作提出了Nojiri-Odintsov全息暗能量的统一处理，包括其Ricci-Gauss-Bonnet实现和二阶近似作为广义框架的特殊情况。通过引入gaus - bonnet不变量和Ricci标量的高阶曲率修正，我们构建了一个扩展的HDE模型，并研究了相互作用和非相互作用情况下状态方程参数的演化。通过宇宙天文钟和普朗克2018数据集的观测验证，分析揭示了可能的精髓到幽灵的转变。结果表明，高曲率修正的作用为后期宇宙加速提供了一个可行的描述。最后，在ricci - gass - bonnet和nojri - odintsov全息框架中，我们发现重建的wot (z)表现出desi偏好的精粹-幻影交叉，尽管普朗克和SH0ES确定的H0之间的哈勃张力仍然没有解决。

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引用次数: 0

Entanglement generation between Unruh–DeWitt detectors in the de Sitter spacetime — Analysis with complex scalar fields de Sitter时空中Unruh-DeWitt探测器之间的纠缠产生-复标量场分析

IF 3 3区物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY

Annals of Physics

Pub Date : 2025-09-19 DOI: 10.1016/j.aop.2025.170235

Shagun Kaushal , Sourav Bhattacharya

We investigate the entanglement generation or harvesting between two identical, comoving Unruh–DeWitt detectors in the cosmological de Sitter spacetime. The detectors are assumed to be unentangled initially. They are individually coupled to a complex scalar field, which eventually leads to coupling between themselves. Two kinds of complex scalar fields are investigated here — conformally invariant and massless minimally coupled. By tracing out the degrees of freedom corresponding to the scalar, we construct the reduced density matrix for the two detectors, whose eigenvalues characterise transition probabilities between the energy levels of the detectors. We have computed the negativity, quantifying the degree of entanglement generated at late times between the two detectors. The similarities and differences of these results between the aforementioned two kinds of scalar fields have been discussed. We also compare our results with the existing result of the real scalar field, and point out the qualitative differences. In particular, we emphasise that entanglement harvesting is more resilient in scenarios involving complex fields and nonlinear couplings.

我们研究了宇宙德西特时空中两个相同的、共同运动的昂鲁-德维特探测器之间的纠缠产生或收获。假设探测器最初是无纠缠的。它们单独耦合到一个复杂的标量场，最终导致它们之间的耦合。本文研究了两种复标量场——共形不变场和无质量最小耦合场。通过追踪对应于标量的自由度，我们构建了两个探测器的简化密度矩阵，其特征值表征了探测器能级之间的跃迁概率。我们已经计算了负性，量化了两个探测器在后期产生的纠缠度。讨论了上述两类标量场结果的异同。并将所得结果与已有的实标量场结果进行了比较，指出了两者质的区别。我们特别强调，在涉及复杂场和非线性耦合的情况下，纠缠收获更具弹性。

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引用次数: 0

Gauge symmetry and partially Lagrangian systems 规范对称与部分拉格朗日系统

IF 3 3区物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY

Annals of Physics

Pub Date : 2025-09-18 DOI: 10.1016/j.aop.2025.170236

S.L. Lyakhovich, N.A. Sinelnikov

We consider a classical field theory whose equations of motion follow from the least action principle, but the class of admissible trajectories is restricted by differential equations. The key element of the proposed construction is the complete gauge symmetry of these additional equations. The unfree variation of the trajectories reduces to the infinitesimal gauge symmetry transformation of the equations restricting the trajectories. We explicitly derive the equations that follow from the requirement that this gauge variation of the action vanishes. The system of equations for conditional extrema is not a Lagrangian system as such, but it admits an equivalent Hamiltonian formulation with a non-canonical Poisson bracket. The bracket is degenerate, in general. Alternatively, the equations restricting the dynamics could be added to the action with Lagrange multipliers with unrestricted variation of the original variables. In this case, we would arrive at the Lagrangian equations for the original variables involving Lagrange multipliers and for Lagrange multipliers themselves. In general, these two methods are not equivalent because the multipliers can bring extra degrees of freedom compared to the case of equations derived by unfree variation of the action. We illustrate the general method with two examples. The first example is a particle in a central field with varying trajectories restricted by the equation of conservation of angular momentum. The phase space acquires one more dimension, and there is an extra conserved quantity

K

which is responsible for the precession of trajectories.

K = 0

corresponds to the trajectories of usual Lagrangian dynamics. The second example is linearized gravity with the Einstein–Hilbert action, and the class of varying fields is restricted by the linearized Nordström equation. This conditional extrema problem is shown to lead to the linearized Cotton gravity equations.

考虑一个经典场论，其运动方程遵循最小作用原理，但可容许轨迹的类别受微分方程的限制。所提出的构造的关键要素是这些附加方程的完全规范对称。轨迹的非自由变分可归结为约束轨迹的方程的无穷小规范对称变换。我们明确地推导出了根据作用的规范变化消失这一要求所推导出的方程。条件极值的方程组不是拉格朗日方程组，但它承认一个带非正则泊松括号的等效哈密顿公式。一般来说，括号是简并的。或者，限制动力学的方程可以用拉格朗日乘子加到作用中，原始变量的变化不受限制。在这种情况下，我们会得到包含拉格朗日乘数的原始变量的拉格朗日方程以及拉格朗日乘数本身的拉格朗日方程。一般来说，这两种方法是不等价的，因为与由作用的非自由变化导出的方程相比，乘数可以带来额外的自由度。我们用两个例子来说明一般方法。第一个例子是中心场中的一个粒子，它的运动轨迹受角动量守恒方程的限制。相空间获得了更多的维度，并且有一个额外的守恒量K，它负责轨迹的进动。K=0对应于通常拉格朗日动力学的轨迹。第二个例子是引力与爱因斯坦-希尔伯特作用的线性化，变化场的类别受到线性化Nordström方程的限制。这个条件极值问题可以得到线性化的Cotton重力方程。

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引用次数: 0

Anisotropic modifications of Gravitational dynamics: Implications for singularity and Cosmic No-Hair theorem via Raychaudhuri equation 引力动力学的各向异性修正：通过Raychaudhuri方程对奇点和宇宙无毛定理的启示

IF 3 3区物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY

Annals of Physics

Pub Date : 2025-09-18 DOI: 10.1016/j.aop.2025.170230

Madhukrishna Chakraborty , Subenoy Chakraborty

The paper deals with the modified Raychaudhuri equation (RE) and convergence of a congruence of time-like geodesics in anisotropic background. The analysis has been compared and contrasted with the isotropic case. Presence of anisotropy in early universe and its effect in the initial big-bang singularity has been discussed using the Raychaudhuri equation corresponding to shear (

σ

) and expansion (

Θ

). Further, the Harmonic oscillator form of the RE has been invoked and effect of anisotropy in convergence has been discussed. Additionally, the effect of anisotropy in determining cosmological dynamics has also been presented using the analytic solution of RE and a justification to Cosmic No Hair conjecture has been given in light of the present analysis. Finally, quantum gravitational aspects by formulating a Wheeler-DeWitt equation based on the anisotropic Raychaudhuri framework has been explored which offers a probabilistic criterion for singularity avoidance and quantum corrections to the cosmic evolution.

本文讨论了各向异性背景下改进的Raychaudhuri方程（RE）和类时测地线同余的收敛性。并与各向同性情况进行了比较。利用与剪切（σ）和膨胀（Θ）相对应的Raychaudhuri方程，讨论了早期宇宙中各向异性的存在及其对初始大爆炸奇点的影响。在此基础上，引入了谐振子形式，并讨论了各向异性对收敛的影响。此外，本文还利用正则表达式的解析解给出了各向异性在确定宇宙动力学中的作用，并据此对宇宙无毛猜想给出了证明。最后，通过建立基于各向异性Raychaudhuri框架的Wheeler-DeWitt方程，探讨了量子引力方面的问题，为宇宙演化的奇点避免和量子修正提供了一个概率准则。

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引用次数: 0

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