Cyclic identities involving Jacobi elliptic functions

Abstract

We state and discuss numerous new mathematical identities involving Jacobi elliptic functions sn(x,m), cn(x,m), and dn(x,m), where m is the elliptic modulus parameter. In all identities, the arguments of the Jacobi functions are separated by either 2K(m)/p or 4K(m)/p, where p is an integer and K(m) is the complete elliptic integral of the first kind. Each p-point identity of rank r involves a cyclic homogeneous polynomial of degree r (in Jacobi elliptic functions with p equally spaced arguments) related to other cyclic homogeneous polynomials of degree r−2 or smaller. We algebraically demonstrate the derivation of several of our identities for specific small values of p and r by using standard properties of Jacobi elliptic functions. Identities corresponding to higher values of p and r are verified numerically using advanced mathematical software packages.