Figure 3.
TSP solutions obtained by the amoeba-based computing system. (a–e) Examples of four-, five-, six-, seven- and eight-city TSP tours obtained in the experiments, where each tour is coloured red in the corresponding map in figure 2. Left panels show transmitted light images of initial states. All branches of the plasmodium (dark orange) were about to enter the lanes (light orange), taking the value Xvk ≃ 0.0. Blue trapezoids indicate the illuminated regions. For n < 8, 64 − n2 lanes of the chip were disabled by applying constant illuminations, as indicated by blue trapezoids on unlabelled lanes. Right panels indicate digitally processed images of satisfactory short tours found by the elongated branches of the plasmodium, where each red and yellow pixel indicates that the thickness of the corresponding region of the plasmodium increased or decreased, respectively.