According to some philosophies of physics, there isn't a difference between the two things you just said. Traveling backwards through time is a valid, experimen

According to some philosophies of physics, there isn't a difference between the two things you just said. Traveling backwards through time is a valid, experimentally consistent, and self-consistent interpretation of a physical phenomenon. If you're not satisfied that means that it's "really" happening, then I think you'll need to be more specific about what you think "truth" means. Spoiler: physics makes your brain hurt. For example, I hear that that are small enough time/distance scales where causality because mathematically ill-defined.