Dark Matter Could Decay into Gravitons and Glow as Gamma Rays
A new proposal suggests dark matter may decay into gravitons, which could convert to photons via the Gertsenshtein effect as they travel through large-scale magnetic fields in intergalactic filaments, producing an excess gamma-ray signal. If true, this would shift searches from galactic centers to intergalactic space and could be tested with Fermi data today, with future missions like the Advanced Particle-astrophysics Telescope boosting sensitivity by an order of magnitude.