a b s t r a c tWe present both simulated and partial empirical evidences for the computational utility of many connected vesicle analogues of an encapsulated nonlinear chemical processing medium. By connecting small vesicles containing a solution of sub-excitable Belousov-Zhabotinsky (BZ) reaction, sustained and propagating wave fragments are modulated by both spatial geometry, network connectivity and their interaction with other waves. The processing ability is demonstrated through the creation of simple Boolean logic gates and then by the combination of those gates to create more complex circuits.

A sub‐excitable Belousov–Zhabotinsky medium exhibits localized travelling excitations (in contrast to an excitable medium exhibiting target or spiral waves). Initially assymetric perturbations give birth to excitation wave‐fragments. The shape and velocity vectors of the wave‐fragments are conserved, meaning they can travel for substantial distances in the reaction media. When the wave‐fragments collide they may reflect, merge, or annihilate. We interpret wave‐fragments as values of logical variables, and the post‐collision states of the fragments as outputs of logical gates. We show how to cascade logical gates in primitive arithmetical circuits.

We introduce results of computer experiments on information processing in a hexagonal array of vesicles filled with Belousov-Zhabotinsky (BZ) solution in a sub-excitable mode. We represent values of Boolean variables by excitation wave-fragments and implement basic logical gates by colliding the wave-fragments. We show that a vesicle filled with BZ mixture can implement a range of basic logical functions. We cascade BZ-vesicle logical gates into arithmetic circuits implementing addition of two one-bit binary numbers. We envisage that our theoretical results will be applied in chemical laboratory designs of massive-parallel computers based on fine-grained compartmentalisation of excitable chemical systems.

Excitation waves on a subexcitable Belousov-Zhabotinsky (BZ) substrate can be manipulated by chemical variations in the substrate and by interactions with other waves. Symbolic assignment and interpretation of wave dynamics can be used to perform logical and arithmetic computations. We present chemical analogs of elementary logic and arithmetic circuits created entirely from interconnected arrangements of individual BZ encapsulated cell-like disk. Interdisk wave migration is confined in carefully positioned connecting pores. This connection limits wave expansion and unifies the input-output characteristic of the disks. Circuit designs derived from numeric simulations are optically encoded onto a homogeneous photosensitive BZ substrate.

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