Overview
- Researchers from Goethe University Frankfurt and the Tsung-Dao Lee Institute report in Nature Astronomy a universal, simulation-backed approach to compare black-hole shadow images across competing gravity theories.
- The method uses the Konoplya–Rezzolla–Zhidenko parametrization with full 3D general-relativistic (magneto)hydrodynamic and radiative-transfer simulations to produce synthetic images for many model variants.
- Resolution-dependent signatures—differences in shadow size and shape, ring brightness asymmetry, and jet width—emerge relative to the Kerr solution predicted by general relativity.
- The analysis indicates that model discrimination requires sub-microarcsecond resolution and percent-level image fidelity, with image mismatches of roughly 2% to 5% needed for robust separation.
- Existing EHT images are consistent with general relativity and mostly exclude only extreme scenarios, while the planned ngEHT and the proposed Black-Hole Explorer are cited as paths to the needed performance.