I think this might be dumb, but, what if negative mass was just positive mass in some alternative dimension? If mass could be negative with respect to our obser

I think this might be dumb, but, what if negative mass was just positive mass in some alternative dimension? If mass could be negative with respect to our observable space time, does that actually mean it is a binary kind of thing, or could there be lots of mass in lots of others semi-or-non-interacting dimensions? Maybe even the mass we can observe is only part of anything’s actual substance...