“…In this section, we will show that ∆-Chow varieties of index (n, d, s, r) exist for all chosen n, d, s, r. Similar to the ordinary differential case, the main idea is to first definably embed G (n,d,s,r) into a finite disjoint union C of the chosen algebraic Chow varieties and then show the image of G (n,d,s,r) is a definable subset of C. So, the language from model theory of partial differentially closed fields (see [21,24,27]) will be used and we assume E is a ∆-closed field of characteristic 0 (i.e., E |= DCF 0,m ) throughout this section.…”