标题： 可穿越的虫洞具有多个不稳定的临界曲线 显示英文标题

标题： Traversable wormholes with multiple unstable critical curves

摘要： 不稳定临界曲线的数量和位置，以及围绕致密天体的吸积盘的性质，在它们的光学外观中起着基础性作用。 识别各种观测到的致密天体的光学光谱差异有助于将它们分类为黑洞或黑洞模仿者，例如可穿越虫洞。 尽管已在非对称可穿越虫洞中报告过多个不稳定临界曲线，但在本工作中我们构建了具有多个不稳定临界曲线的对称可穿越虫洞。 我们提出了一种一般的有理红移函数，使我们能够追踪有效势的临界点数量并确定它们是极大值还是极小值。 使用光线追踪方法来研究无质量粒子的轨迹，特别是它们在不稳定临界点附近的的行为。 最后，实施了一个薄吸积盘模型来分析该解的光学外观。 显示英文摘要

摘要： The number and position of unstable critical curves, as well as the nature of the accretion disk around compact objects, play a fundamental role in their optical appearance. Identifying differences in the optical spectrum of various observed compact objects can help classify them as black holes or black hole mimickers, such as traversable wormholes. Although multiple unstable critical curves have been reported to appear in asymmetric traversable wormholes, in this work we construct symmetric traversable wormholes with multiple unstable critical curves. We propose a general rational redshift function that allows us to trace the number of critical points of the effective potential and determine their nature as maxima or minima. The ray tracing method is used to study the trajectories of massless particles, particularly their behavior near the unstable critical points. Finally, a thin accretion disk model is implemented to analyze the optical appearance of the solution.