Microlensing effects of wormholes associated to blackhole spacetimes

TL;DR

This paper explores how different types of wormholes and black holes affect gravitational microlensing, revealing distinctive multi-peak magnification patterns that could help distinguish these objects observationally.

Contribution

It provides a comparative analysis of microlensing effects of Schwarzschild, Kerr, and Reissner-Nordström wormholes and black holes, highlighting unique features like multi-peak magnification.

Findings

Kerr wormholes can produce multi-peak magnification in prograde cases.

Kerr black holes predict a single peak in magnification.

Reissner-Nordström wormholes can have negative magnification in some situations.

Abstract

In this paper, we investigate the microlensing effects of wormholes associated to black hole spacetimes. Specifically, we work on three typical wormholes (WH): Schwarzschild WH, Kerr WH, and RN WH, as well as their blackhole correspondences. We evaluate the deflection angle upon the second order under weak field approximation using Gauss-Bonnet theorem. Then, we study their magnification with numerics.We find that a Kerr WH could lead to multi peaks in the magnification with certain parameters in the prograde case, while a Kerr BH predicts one peak. Therefore, the multi-peak feature of can be used to distinguish the Kerr WH from other compact objects. We also find that the magnification of RN BH will be one peak compared to RN WH, in which the magnification of RN WH is negative in some situations. For other cases, the behavior of magnification from wormholes and their corresponding blackholes is similar. Our result may shed new light on exploring compact objects through the microlensing effect.