Figure 14

Cell-cell interaction. The Greens function for the interaction between particles a and b at positions ${\mathbf{x}}_a$ and ${\mathbf{x}}_b$ and residing in cells A and B, is approximated by Taylor expanding the Greens function about r, the distance vector between the cell centres ${\mathbf{z}}_A$ and ${\mathbf{z}}_B$.