标题： 广义Rastall引力中的虫洞解 显示英文标题

标题： Wormhole solutions in generalized Rastall gravity

摘要： 在本工作中，我们寻求静态球对称解，这些解在广义Rastall引力（GRG）中表示虫洞配置。 在该理论中，变化的耦合参数可以作为暗能量（DE），因此可以认为它负责宇宙当前的加速膨胀。 我们考虑各向异性能量动量张量（EMT）作为虫洞结构的支持源，并进一步假设径向和切向压力与能量密度之间存在线性关系。 因此，我们得到GRG场方程的两类解，包括具有零和非零红移函数的解。 对于这些解，我们发现物质分布满足物理合理性条件，即在喉部和整个时空中的flare-out以及弱能条件（WEC）和零能条件（NEC）。 虫洞解的物理合理性条件对模型参数施加了限制。 因此，在GRG框架下，可以构建渐近平坦的虫洞配置，而无需使用奇异物质。 还讨论了所得解的引力透镜效应，发现虫洞的喉部可以有效地作为光子球，靠近该光子球时，光线偏转角可以取任意大的值。 显示英文摘要

摘要： In the present work, we seek for static spherically symmetric solutions representing wormhole configurations in generalized Rastall gravity (GRG). In this theory, a varying coupling parameter could act as dark energy (DE) and thus, it can be considered as responsible for the current accelerated expansion of the universe. We consider an anisotropic energy momentum tensor (EMT) as the supporting source for wormhole structure and further assume that there exists a linear relation between radial and tangential pressures and energy density. We therefore obtain two classes of solutions to the field equations of GRG, including the solutions with zero and nonzero redshift functions. For these solutions we find that the matter distribution obeys the physical reasonability conditions, i.e., the flare-out and the weak (WEC) and null (NEC) energy conditions either at the throat and throughout the spacetime. The conditions on physical reasonability of the wormhole solutions put restrictions on model parameters. Hence, in the framework of GRG, asymptotically flat wormhole configurations can be built without the need of exotic matter. Gravitational lensing effects of the obtained solutions are also discussed and it is found that the throat of wormhole can effectively act as a photon sphere near which the light deflection angle takes arbitrarily large values.