On the trajectories of null and timelike geodesics in different wormhole geometries

TL;DR

This paper provides a comprehensive analysis of null and timelike geodesics in various wormhole geometries, including static, dynamic, and rotating cases, using the invariant angle method to understand photon trajectories.

Contribution

It offers a detailed study of geodesic behaviors in different wormhole models, including photon spheres and orbit types, extending previous analyses to dynamic and rotating wormholes.

Findings

Photon spheres identified in Morris-Thorne wormholes.

Bounded and unbounded timelike orbits characterized.

Angles between vectors on photon trajectories calculated.

Abstract

The paper deals with an extensive study of null and timelike geodesics in the background of wormhole geometries. Starting with a spherically symmetric spacetime, null geodesics are analyzed for the Morris-Thorne wormhole(WH) and photon spheres are examined in WH geometries. Both bounded and unbounded orbits are discussed for timelike geodesics. A similar analysis has been done for trajectories in a dynamic spherically symmetric WH and for a rotating WH. Finally, the invariant angle method of Rindler and Ishak has been used to calculate the angle between radial and tangential vectors at any point on the photon's trajectory.