Streaming sand grains help define essence of a liquid

In this high-speed, high-resolution video, freely falling granular streams behave similarly to water flowing from a faucet. These granular streams behave like dense, cold fluids with ultra-low surface tension (cohesion between individual molecules). 'These experimental results open up new territory for which there currently is no theoretical framework,' John Royer and his co-authors at the University of Chicago report in the journal Nature (c) John Royer

Tags: behaviour, grain, liquid, molecule, surface, tension