In the mid to late 1920s, the emerging theory of quantum mechanics had two main competing (and, initially, mutually antagonistic) formalisms — the wave mechanics of E. Schrödinger [61] and the matrix mechanics of W. Heisenberg, M. Born and P. Jordan [27][2][3].¹ Though a connection between the two was quickly pointed out by Schrödinger himself — see paper III in [61] — among others, the folk-theoretic "equivalence" between wave and matrix mechanics continued to generate more detailed study, even into our times.