作为常规黑洞、黑洞弹跳及标量毛发致密天体探针的红移光谱学
Redshift Spectroscopy as a Probe of Regular Black Holes, Black Bounces, and Scalar-Hair Compact Objects
- Eastern Mediterranean University（东地中海大学）
- Mapúa University（马普阿大学）
- Pontificia Universidad Católica de Valparaíso（天主教瓦尔帕莱索宗座大学）
机构由 AI 辅助整理，请以论文原文为准。
中文总结 AI 辅助
该研究开发了适用于静态球对称时空的统一模型无关红移光谱学框架，推导了相关守恒量与频率偏移表达式，应用于三类致密天体模型，可跨多个天体领域使用该光谱学语言。
中文摘要 AI 辅助
受[Phys. Rev. D. 107, 064019 (2023)]启发，我们为一般静态球对称时空中的光子频率偏移光谱学开发了一个统一且与模型无关的框架。采用由三个任意径向度规函数表征的线元，我们推导了有质量和无质量探测器的守恒量、类时圆轨道的条件、与本地发射角相关的光子碰撞参数，以及遥远静态观测者测得的相应本地红移和蓝移分支。该形式主义进一步扩展至包含源的视线方向本动及光子在非磁化冷等离子体中的本地传播，从而确定了所述假设下频率偏移信号中的引力、轨道和色散因子。我们还证明，在真空中，只要存在外部零测地线临界轨道，支配轨道光谱学的相同几何结构就决定了光子球和阴影碰撞参数。为使该框架适用于变形致密天体模型，我们在史瓦西几何周围构建了微扰展开，直至无量纲形变参数的二阶项，得到了轨道能量、角动量、发射体四速度、光子碰撞参数以及真空和等离子体频率偏移的显式修正项。我们将该形式主义应用于非线性电动力学产生的常规黑洞、Simpson--Visser黑洞弹跳时空以及Fisher--Janis--Newman--Winicour--Wyman几何。这些例子表明，相同的本地光谱学语言可用于常规黑洞、黑洞弹跳、虫洞及标量支撑的无视界天体领域。
英文摘要
Motivated by [Phys. Rev. D. 107, 064019 (2023)], we develop a unified and model-independent framework for the spectroscopy of photon frequency shifts in generic static, spherically symmetric spacetimes. Working with a line element characterized by three arbitrary radial metric functions, we derive exact expressions for the conserved quantities of massive and massless probes, the conditions for circular timelike geodesics, the local-emission-angle-dependent photon impact parameter, and the corresponding local redshift and blueshift branches measured by distant static observers. The formalism is further extended to include the line-of-sight peculiar motion of the source and the local propagation of photons in a nonmagnetized cold plasma, thereby identifying the gravitational, orbital, and dispersive factors entering the frequency-shift signal under the stated assumptions. We also show that, in vacuum, the same geometric structures governing orbital spectroscopy determine the photon sphere and the shadow impact parameter whenever an external null critical orbit is present. To make the framework suitable for deformed compact-object models, we construct a perturbative expansion around Schwarzschild geometry up to second order in a dimensionless deformation parameter, obtaining explicit corrections to the orbital energy, angular momentum, emitter four-velocity, photon impact parameter, and the vacuum and plasma frequency shifts. We apply the formalism to regular black holes from nonlinear electrodynamics, the Simpson--Visser black-bounce spacetime, and the Fisher--Janis--Newman--Winicour--Wyman geometry. These examples show that the same local spectroscopic language can be used across regular-black-hole, black-bounce, wormhole, and scalar-supported horizonless sectors.
