Huh, interesting. I just tried meditating on vector space duality for 5 minutes, and it was joyful in some sense but not quietly so - I experienced a lot of movement in my body, in a way that feels similar to reactions I've been having to really good music or beautiful visual scenes lately. Something was agonizing about it and I wanted to stop so I could get on with the business of living or something, but that might be mostly because I'm feeling under time pressure lately.

I came to a similar conclusion a couple years ago, though I'm less certain of it now. I think you're correct that math is dual to the kinds of self-dialogue (or observation) that people normally have while meditating, but I think that's just a quirk of how people normally meditate.

When most people meditate, their thoughts are fairly free-form and unstructured. You can make them a bit more guided by top-down giving them some structure. When I do this, my meditative thoughts start coming in more structured bits, often through visuals.

You can do this with different structures. For example you can try imposing intention (as in "X intends to do Y", or "X intended to say Z") to your meditative thoughts.

I think this is closer to daydreaming than meditation. I won't contest that daydreaming about math is a great deal of fun.

Maybe you should do it with paper and a working utensils - I can't really do math without external memory, and other people including you are probably bad at it to.