Observational signatures of negative mass wormholes through their shadows

We investigate systems containing objects with negative mass (NMOs). In a system consisting of one object with positive mass and one NMO, a bound state exists even though the force exerted by the NMO on the object with positive mass is repulsive. Unlike a standard system consisting of two objects with positive mass, the gravitational waves emitted from this system exhibit a decrease in frequency and amplitude over time. We propose a model of the time evolution of the Ellis-Bronnikov wormhole, along with a formulation that eliminates the ghost that appears when constructing the Ellis-Bronnikov wormhole, a candidate for an NMO. Furthermore, numerical simulations are performed to obtain the optical appearance of such NMOs. The observed luminosity is also compared with the Schwarzschild black hole and with the Simpson-Visser wormhole, leading to clear differences in the photon ring substructure around the central object.