We never get a clear view of the entire mirror but while I see a couple of things that look like they might be response functions in statistical mechanics, an equation that might be definition of characteristic temperature, what appears to be a Feynman diagram in the lower right corner, and a bunch of random words like “divergence” and “fermions”, it does look like just random equations they got someone to write on the mirror. While I could only stand to listen to the clip twice, the dialogue is even worse and the entire idea of “super asymmetry” is pure technogibberish.
Writing out the formulation for even a very basic interaction for two superstrings would take at up at least a page on one of those giant landscape sketchbook, and in fact in the time before there were computer algebra systems that could handle systems that complex it was a cachet among physics grad students working on M-theory to carry these awkward things around (presumably in imitation of Ed Witten who would reportedly walk around Harvard and later Institute of Advanced Study with such a notebook). You can’t expect a sitcom to shoot for technical accuracy, of course, but the idea that a couple of people would come up with a profoundly unique theory of everything that would fit onto a mirror written in lipstick is obviously absurd (as I’m sure it was intended to be).