Higher-order correction to weak-field lensing of an Ellis-Bronnikov wormhole

Understand

The gravitational lensing effect at higher order under weak-field approximation is believed to be important to distinguish black holes and other compact objects such as wormholes.

• The deflection angle of a generic wormhole is difficult to solve analytically; thus approximation methods are implemented.
• In this paper, we investigate the weak-field deflection angle of a specific wormhole, the Ellis-Bronnikov wormhole, up to the 1/b^4 order.
• We use different approximation formalisms, study their precision at 1/b^4 order by a comparison to a purely numerical result, and finally rank these formalisms by their accuracy.