Stability and pulsation of the first dark stars

The role of residual symmetries in dark matter stability and the neutrino nature

We consider the class of models where Dirac neutrino masses at one loop and the dark matter stability can be obtained using only the global $U(1)_{B-L}$ symmetry already present in Standard Model. We discuss how the residual $\mathcal{Z}_n$ subgroup, left unbroken after the breaking of $U(1)_{B-L}$, dictates the neutrino nature, namely if they are Dirac or Majorana particles, as well as determines the stability of the dark matter candidate in such models. In particular, we show that without the correct breaking of $U(1)_{B-L}$ to an appropriate residual $\mathcal{Z}_n$ symmetry, the Dirac natu…

从轻子质量看狄拉克中微子与暗物质稳定性

Dirac Neutrinos and Dark Matter Stability from Lepton Quarticity

我们建议将暗物质稳定性与中微子的狄拉克性质联系起来。这个想法是说明在一个简单的计划，小狄拉克中微子质量产生的I型跷跷板机制作为一个$Z_4$离散轻子数对称性的结果。后者意味着存在一个可行的WIMP暗物质候选者，其稳定性源于确保中微子Dirac性的相同对称性。

Challenging the Stability of Light Millicharged Dark Matter

We investigate the cosmological stability of light bosonic dark matter carrying a tiny electric charge. In the wave-like regime of high occupation numbers, annihilation into gauge bosons can be drastically enhanced by parametric resonance. The millicharged particle can either be minimally coupled to photons or its electromagnetic interaction can be mediated via kinetic mixing with a massless hidden photon. In the case of a direct coupling current observational constraints on the millicharge are stronger than those arising from parametric resonance. For the (theoretically preferred) case of kin…

剩余味对称性导致的暗物质稳定性

Dark Matter Stability from residual flavour symmetries

该研究提出模型无关框架，利用连续味对称性自发破缺后剩余的离散对称性实现暗物质自然稳定，无需特设稳定对称性，还构建原型模型结合味物理与暗物质研究。

Study of thermal stability for different dark energy models

In the present work, we have made an attempt to investigate the dark energy possibility from the thermodynamical point of view. For this purpose, we have studied thermodynamic stability of three popular dark energy models in the framework of an expanding, homogeneous, isotropic and spatially flat FRW Universe filled with dark energy and cold dark matter. The models considered in this work are Chevallier-Polarski-Linder (CPL) model, Generalized Chaplygin Gas (GCG) model and Modified Chaplygin Gas (MCG) model. By considering the cosmic components (dark energy and cold dark matter) as perfect flu…

通过宇宙结构的稳定性约束暗能量

Constraining Dark Energy through the Stability of Cosmic Structures

对于一般的暗能量状态方程，我们估计的最大可能半径的大规模结构，不稳定的宇宙膨胀的加速。与已知的稳定结构的比较约束状态方程。通过积累更多的天体物理学数据和更好地了解束缚宇宙结构的动力学，可以加强约束的鲁棒性。

Ricci暗能量的标量微扰与稳定性

Scalar Perturbation and Stability of Ricci Dark Energy

为了解释宇宙加速膨胀而提出的里奇暗能量（RDE）需要它的参数$α< 1$，该参数的值将决定RDE的行为。本文研究了宇宙中有无物质时RDE的标量微扰，发现在这两种情况下，当$α> 1/3$满足时，微扰都是稳定的，从而从理论上给出了$α$的一个下界.

On the Stability of Fermionic Non-Isothermal Dark Matter Halos

The stability of isothermal dark matter halos has been widely studied before. In this paper, we investigate the stability of non-isothermal fermionic dark matter halos. We show that in the presence of temperature gradient, the force due to the pressure has both inward and outward components. In some regions of halos, the inward force that provides stability is due to the pressure rather than gravity. Moreover, it is shown that higher temperature gradients lead to halos with lower mass and size. We prove that if the temperature is left as a free positive profile, one can place no phase-space lo…

模糊暗物质多态构型的稳定性

Stability of multi-state configurations of fuzzy dark matter

本研究通过数值模拟和稳定性准则，证明了无自相互作用的薛定谔-泊松系统中含单极和偶极分量的多态构型是稳定的，为多态超轻玻色子暗物质提供了物理合理性支持。