In 2012, along with physicist Troy Shinbrot of Rutgers University, New Jersey, he managed to replicate the observation. The team used two large tanks placed next to each other. One was one centimetre higher than the other, with a channel running from one to the other.They added chalk and the Cuban mate tea leaves that Mr Bianchini used to the bottom tank. Within a few seconds, particles headed up the channel to the upper tank.
It is thought by the physicists that this phenomenon is due to the surface tension of the downstream water. When it’s disturbed by particles, it can produce the force that pushes them upstream. This knowledge could have practical applications – such as demonstrating that rogue particles could sneak into pipettes used for scientific experiments, or back into clean water after waste has been discharged. And to think, this all started with a cup of loose leaf tea.
Next time you make a cup of tea, remember you could be defying physics.