It’s time to feed the blob. Foaming and voracious, it sucks up eight plate-sized portions every few seconds. What we refer to as a blob here is a stable, turbulent speck in a giant water tank in the laboratory of physicist William Irvine at the University of Chicago.
In contrast to all previously observed turbulence, it is not a diffuse swirling flow that increases or decreases over time. Instead, the blob resembles a self-contained, seething ball that does not move the water around it. In order to create and, in particular, maintain the unusual phenomenon, Irvine and his doctoral student Takumi Matsuzawa have to bombard it with eight annular vortices, the liquid counterpart to smoke rings, over and over again. “This is how we build up the turbulence bit by bit,” explains Matsuzawa.
Because the two researchers control the ring-shaped eddies very precisely, they can examine the resulting turbulence up close. The blob could thus provide insights into a chaotic world that physicists have been chasing for more than two centuries …
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