发表机构
Pontificia Universidad Católica de Valparaíso; Universidad de Santiago de Chile; Universidad del Bío-Bío（天主教瓦帕莱索大学; 智利圣地亚哥大学; 比奥比奥大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
研究单模引力和广义相对论中可穿越虫洞的区别，通过分析静态球对称解的嵌入和测地线，比较维持相同几何的源部分，发现UG与GR几何等效但源部分动力学有别，不同引力理论时空几何相同但维持源不同。
AI 中文摘要
我们刻画了单模引力（UG）中的可穿越虫洞，并研究它们与广义相对论（GR）对应物的区别。对于一类静态球对称解，我们分析其嵌入和类时测地线，表明测地线结构完全由度规决定，在两种理论中相同。为确定差异的物理起源，我们比较维持相同虫洞几何所需的源部分。发现保持固定UG几何同时施加能量动量守恒需要限制状态方程，放松此条件会引入有效的非均匀真空贡献。我们还表明，即使能量动量不守恒，奇异程度也会保留，与GR部分的差异编码在有效的非均匀真空结构中，其渐近行为类似于宇宙常数。我们的结果强化了UG在几何上等同于GR，而其独特特征出现在源部分的动力学解释中。更一般地，我们的分析表明不同引力理论可能产生相同时空几何，但需要不同源来维持它们。
英文摘要
We characterize traversable wormholes in Unimodular Gravity (UG) and investigate what distinguishes them from their General Relativistic (GR) counterparts. For a class of static and spherically symmetric solutions, we analyze their embedding and timelike geodesics, showing that the geodesic structure is entirely determined by the metric and is therefore identical in both theories. To identify the physical origin of their differences, we compare the source sectors required to sustain the same wormhole geometry. We find that preserving a fixed UG geometry while imposing energy-momentum conservation requires restricting the equation of state, whereas relaxing this condition introduces an effective inhomogeneous vacuum contribution. We further show that the degree of exoticity is preserved even when energy-momentum is not conserved, while departures from the GR sector are encoded in an effective inhomogeneous vacuum structure whose asymptotic behavior resembles that of a cosmological constant. Our results reinforce that UG is geometrically equivalent to GR, while its distinctive features emerge in the dynamical interpretation of the source sector. More generally, our analysis illustrates that different gravitational theories may give rise to identical spacetime geometries while requiring different sources to sustain them.
CommentsAccepted for publication in European Physical Journal C
