发表机构
Universidade Federal do Ceará (UFC); Instituto de Física Corpuscular (IFIC), CSIC-Universitat de València; Faculdade de Física, Campus Salinópolis, Universidade Federal do Pará（塞阿拉联邦大学; 瓦伦西亚大学-CSIC粒子物理研究所; 帕拉州联邦大学萨利诺波利斯校区物理学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
研究黑洞弹跳几何的轴向引力扰动与阴影，发现视界构型类似标准黑洞，无视界对称构型产生引力波回波和多重光子环，非对称构型无回波但保持雷斯勒-诺德斯特伦特征。
AI 中文摘要
我们研究了广义相对论中各向异性流体支撑的黑洞弹跳几何中的轴向引力扰动和阴影形成。分析了两类不同的解：对称的类辛普森-维瑟黑洞弹跳和雷斯勒-诺德斯特伦度规的非对称变形，后者可以具有有界内部区域或无界类虫洞延伸。我们的发现表明，具有视界的构型，无论对称还是非对称，都表现出单势垒有效势和准正则频率，与标准黑洞几乎无法区分。相比之下，无视界对称构型可能发展出多个势垒，产生引力波回波，其振幅和间隔敏感地依赖于弹跳参数 $a$ 和密度参数 $\ ho_0$。另一方面，无视界非对称解表现出正则化的有效势，不产生回波，且在现象学上仍接近雷斯勒-诺德斯特伦情形。从光学角度看，两类具有视界的解都表现出单一相关光子球和阴影轮廓，与其黑洞对应物几乎无法区分，而无视界对称构型可以维持多个光子环。无视界非对称构型则可能支持单个光子环或没有光子环。最后，对于具有视界的构型，我们恢复了准正则模式与圆零测地线不稳定性之间的标准程函对应关系。然而，对于无视界几何，多个势垒的出现阻止了这种关系的直接扩展，尽管波和光学领域之间的强烈相似性表明，有意义的唯象对应关系可能仍然存在。
英文摘要
We investigate axial gravitational perturbations and shadow formation in black-bounce geometries supported by anisotropic fluids within general relativity. Two distinct classes of solutions are analyzed: a symmetric Simpson--Visser-like black bounce and an asymmetric deformation of the Reissner--Nordström metric, which can feature either a bounded interior region or an unbounded wormhole-like extension. Our findings indicate that configurations with horizons, whether symmetric or asymmetric, exhibit single-barrier effective potentials and quasinormal frequencies nearly indistinguishable from those of standard black holes. In contrast, horizonless symmetric configurations may develop multiple potential barriers, giving rise to gravitational-wave echoes whose amplitude and separation depend sensitively on the bounce parameter $a$ and the density parameter $ρ_0$. Horizonless asymmetric solutions, on the other hand, exhibit regularized effective potentials that do not produce echoes and remain phenomenologically close to the Reissner--Nordström case. From the optical perspective, both classes of solutions with horizons exhibit a single relevant photon sphere and shadow profiles nearly indistinguishable from those of their black-hole counterparts, while horizonless symmetric configurations can sustain multiple photon rings. Horizonless asymmetric configurations may instead support either a single photon ring or none. Finally, we recover the standard eikonal correspondence between quasinormal modes and the instability of circular null geodesics for configurations with horizons. For horizonless geometries, however, the emergence of multiple potential barriers prevents a straightforward extension of this relation, although the strong similarity between the wave and optical sectors suggests that a meaningful phenomenological correspondence may still persist.
Comments39 pages, 22 figures, 1 table
