Bacterial computers can crack mathematical problems | Science | guardian.co.uk

The research, published today in the Journal of Biological Engineering, proves that bacteria can be used to solve a puzzle known as the Hamiltonian Path Problem. Imagine you want to tour the 10 biggest cities in the UK – one route might start in London (number 1) and finish in Bristol (number 10), for example. The solution to the Hamiltonian Path Problem would be the route that takes in each city just once.

This simple problem is surprisingly difficult to solve. There are over 3.5 million possible routes to choose from, and a regular computer must try them out one at a time to find the one that visits each city only once. Alternatively, a computer made from millions of bacteria can look at every route simultaneously. The biological world also has other advantages. As time goes by, a bacterial computer will actually increase in power as the bacteria reproduce.