Black holes with Skyrmion-anti-Skyrmion hairs

Skyrmion Black Hole Hair: Conservation of Baryon Number by Black Holes and Observable Manifestations

We show that the existence of black holes with classical skyrmion hair invalidates standard proofs that global charges, such as the baryon number, cannot be conserved by a black hole. By carefully analyzing the standard arguments based on a Gedankenexperiment in which a black hole is seemingly-unable to return the baryon number that it swallowed, we identify inconsistencies in this reasoning, which does not take into the account neither the existence of skyrmion black holes nor the baryon/skyrmion correspondence. We then perform a refined Gedankenexperiment by incorporating the new knowledge a…

Hairy black holes in the general Skyrme model

We study the existence of hairy black holes in the generalized Einstein-Skyrme model. It is proven that in the BPS model limit there are no hairy black hole solutions, although the model admits gravitating (and flat space) solitons. Furthermore, we find strong evidence that a necessary condition for the existence of black holes with Skyrmionic hair is the inclusion of the Skyrme term $\mathcal{L}_4$. As an example, we show that there are no hairy black holes in the $\mathcal{L}_2+\mathcal{L}_6+\mathcal{L}_0$ model and present a new kind of black hole solutions with compact Skyrmion hair in the…

反de Sitter空间中的经典Yang-Mills黑洞头发

Classical Yang-Mills black hole hair in anti-de Sitter space

综述了Einstein-Yang-Mills（EYM）理论中毛状黑洞的性质，重点讨论了球对称解.特别地，在渐近反德西特空间（adS）中，已知su（2）EYM存在稳定的黑洞毛发。我们回顾了最近的工作，它表明，稳定的头发也存在于su（N）EYM任意N，所以有多少稳定的头发在adS中的黑洞可以拥有没有上限。

反德西特空间中黑洞的丰富稳定规范场毛

Abundant stable gauge field hair for black holes in anti-de Sitter space

在渐近反德西特（adS）空间中给出了su（N）Einstein-Yang-Mills理论（EYM）的新的多毛黑洞解.这些黑洞由N+1个独立参数描述，具有N-1个独立的规范场自由度。所有规范场函数都没有零点的解存在于所有N和足够大（且为负）的宇宙学常数中。这些解决方案中的至少一些被证明是稳定的经典，线性，球对称扰动。因此，在adS中的黑洞所能被赋予的稳定规范场头发的数量没有上限。

Superradiant Instability of Near Extremal and Extremal Four-Dimensional Charged Hairy Black Hole in anti-de Sitter Spacetime

We study the instability of near extremal and extremal four-dimensional AdS charged hairy black hole to radial neutral massive and charged massless scalar field perturbations. We solve the scalar field equation by using the improved asymptotic iteration method and the time domain analysis and we find the quasinormal frequencies. For the charged scalar perturbations, we find the superradiance condition by computing the reflection coefficient in the low-frequency limit and we show that in the superradiance regime, which depends on the scalar hair charge, all modes of radial charged massless pert…

Characterizing asymptotically anti-de Sitter black holes with abundant stable gauge field hair

In the light of the "no-hair" conjecture, we revisit stable black holes in su(N) Einstein-Yang-Mills theory with a negative cosmological constant. These black holes are endowed with copious amounts of gauge field hair, and we address the question of whether these black holes can be uniquely characterized by their mass and a set of global non-Abelian charges defined far from the black hole. For the su(3) case, we present numerical evidence that stable black hole configurations are fixed by their mass and two non-Abelian charges. For general N, we argue that the mass and N-1 non-Abelian charges …

具有磁偶极毛的非阿贝尔黑洞

Non-Abelian Black Holes with Magnetic Dipole Hair

在SU（2）Einstein-Yang-Mills-Higgs理论中构造了静态轴对称黑洞。这些黑洞位于一对黑洞和反黑洞之间，拥有磁偶极毛。它们的质量与视界质量之差等于正则反夸克-反夸克解的质量，正如孤立视界框架所预期的那样。

Skyrmion--Anti-Skyrmion Chains

Static axially symmetric sphaleron-type solutions describing chains of interpolating Skyrmion--anti-Skyrmions have been constructed numerically. The configurations are characterized by two integers n and m, where $\pm n$ are the winding numbers of the constituent Skyrmion and anti-Skyrmion and the second integer m defines type of the solution, it has zero topological charge for even m and for odd values of m the Skyrmion--anti-Skyrmion chain has topological charge n. For the vanishing mass term we confirm the existence of such chain solutions for winding number $|n| \ge 2$. The similarity with…

Non-existence of Skyrmion-Skyrmion and Skyrmion-anti-Skyrmion static equilibria

We consider classical static Skyrmion-anti-Skyrmion and Skyrmion-Skyrmion configurations, symmetric with respect to a reflection plane, or symmetric up to a $G$-parity transformation respectively. We show that the stress tensor component completely normal to the reflection plane, and hence its integral over the plane, is negative definite or positive definite respectively. Classical Skyrmions always repel classical Skyrmions and classical Skyrmions always attract classical anti-Skyrmions and thus no static equilibrium, whether stable or unstable, is possible in either case. No other symmetry a…

热黑洞的整体电荷剥离

Depilating Global Charge From Thermal Black Holes

在形式上，把一个全局守恒量子数的化学势引入包含黑洞的时空的配分函数似乎没有什么困难。然而，如果这是可能的，它将提供一种黑洞毛发的形式，并与全球量子数在黑洞蒸发中被破坏的想法相矛盾。我们证明了动力学机制，否定了正式的程序，无论是拓扑电荷（Skyrmions）和复杂的标量场电荷。Skyrmions坍缩到视界;标量场电荷不受控制地波动。

反de Sitter空间引力的重整化群流与黑洞无毛定理

Renormalization Group Flows from Gravity in Anti-de Sitter Space versus Black Hole No-Hair Theorems

黑洞无毛定理证明使用的不等式，支配径向依赖球对称配置的物质场。本文利用AdS/CFT对应分析了与重整化群流对偶的几何的类似不等式。这些不等式提供了许多有用的信息，这种流动的定性性质。对于庞加莱不变流，我们表明，相关或不相关的运营商的通用流导致奇异几何。对于不相关的运营商的情况下，这导致了一个明显的冲突与Polchinski的解耦定理，我们提供了两种可能的解决方案，这个问题。

Baby Skyrmion模型中的介子、重子和波

Mesons, Baryons and Waves in the Baby Skyrmion Model

研究了$(2+1)$维baby-Skyrmion模型的各种经典解.指出了高能态的存在，将其解释为Skyrmion和反Skyrmion的共振态，并研究了它们的衰变。大部分的讨论涉及到一个高度激发的类Skyrmion态，其缠绕数为1，衰变为普通的Skyrmion和Skyrmion-anti-Skyrmion对。我们还研究了该模型的波动解，并表明，一些这样的解决方案可以从正弦戈登方程的解决方案。我们还证明了baby-Skyrmion具有非拓扑定态解。我们研究它们与Skyrmions的相互作用。

Symmetry Analysis of Holes Localized on a Skyrmion in a Doped Antiferromagnet

We use the low-energy effective field theory for holes coupled to the staggered magnetization in order to investigate the localization of holes on a Skyrmion in a square lattice antiferromagnet. When two holes get localized on the same Skyrmion, they form a bound state. The quantum numbers of the bound state are determined by the quantization of the collective modes of the Skyrmion. Remarkably, for p-wave states the quantum numbers are the same as those of a hole-pair bound by one-magnon exchange. Two holes localized on a Skyrmion with winding number $n = 1$ or 2 may have s- or d-wave symmetry…

Domain Wall Skyrmions in Chiral Magnets

Domain wall skyrmions are skyrmions trapped inside a domain wall. We investigate domain wall skyrmions in chiral magnets using a fully analytic approach. Treating the Dzyaloshinskii-Moriya (DM) interaction perturbatively, we construct the low-energy effective theory of a magnetic domain wall in an $O(3)$ sigma model with the DM interaction and an easy-axis potential term, yielding a sine-Gordon model. We then construct domain wall skyrmions as sine-Gordon solitons along the domain wall. We also construct domain wall skyrmions on top of a pair of a domain wall and an anti-domain wall. One of ch…