By Andrew Grant
Water flows best when it’s chock-full of synchronized-swimming bacteria.
By coaxing billions of E. coli to work together, French researchers got a small sample of a bacteria-laden solution to have no resistance to flow, or zero viscosity. Such effortless motion is usually reserved for superfluids like liquid helium that are kept at frigid temperatures.
“The results are pretty compelling,” says Raymond Goldstein, a complex systems physicist at the University of Cambridge. The study, in the July 10 Physical Review Letters, demonstrates how the motion of microscopic organisms can drive the large-scale behavior of liquids.