I have a question. Before I start, I want to say that I know negative mass itself has not been observed or proven to exist, if it does at all. That is why this is more of a what-if question if that is okay. Anyway...
Say an object has negative mass and therefore negative inertia. Now, considering inertial reference frames, or fictitious forces, objects with normal mass appear to move, such as going backwards seemingly when say, a car it is in speeds up. If a negative mass object were to exi