Look at the x,y,z axis. Three dimensions in one quadrant.

There are four quadrants. Antimatter is hanging out in one of the other quadrants.

What about the other two quadrants?

Gravity, which constitutes negative dimensions relative to the  positive dimensions of the  x,y,z axis,  takes up one of the other quadrants.

The fourth quadrant is obviously the dimensions that constitute antimatter’s gravitational force.

Antimatter exists as a potential.  With the introduction of energy, antimatter is produced.

Here. Let me show you.

The positive quadrant (above) constitutes the dimensions of matter.

(z axis not pictured here).

The negative quadrant (below) constitutes the dimensions of  antimatter.