An incredibly fascinating and interesting experiment.
A team of physical chemists and mathematicians built a “chemical navigation system” that, using the Marangoni effect, correctly found a route to a pizzeria in Budapest.
An acidified gel is placed at the destination of a labyrinth filled with alkaline liquid. The acid distributes itself in the still alkaline maze in a short time, but the majority of it remains together with the gel at the destination. If you now give a lye to the other end of the labyrinth, i.e. at the entrance, it is automatically looking for the way to the destination, i.e. the place with the highest acidity.
“Chemical computing” is still in its infancy, but has great potential in brain research, psychology, network research and robotics, since navigation is much faster than with electronic counterparts.