Strong field lensing by Damour-Solodukhin wormhole

TL;DR

This paper studies how Damour-Solodukhin wormholes can mimic black hole lensing signatures in strong gravitational fields, revealing that larger deviations from black holes are possible without detection.

Contribution

It demonstrates that wormholes with deviation parameter values higher than previously expected can produce lensing observables similar to black holes.

Findings

Lensing signatures can be indistinguishable for a range of deviation parameters.

Tiny deviation parameters are not necessary for black hole mimicry.

Lensing observations challenge the assumption that all experiments should confirm black hole nature.

Abstract

We investigate the strong field lensing observables for the Damour-Solodukhin wormhole and examine how small the values of the deviation parameter $\lambda $ need be for reproducing the observables for the Schwarzschild black hole. While the extremely tiny values of $\lambda$ indicated by the matter accretion or Hawking evaporation are not disputed, it turns out that $\lambda $ could actually assume values considerably higher than those tiny values and still reproduce black hole lensing signatures. The lensing observations thus provide a surprising counterexample to the intuitive expectation that all experiments ought to lead to the mimicking of black holes for the same range of values of $\lambda$.