Mathematicians Make the Guinness Widget Redundant

So says an article in The Economist:

The widget’s days, though, may be numbered, for a crack group of mathematicians from the University of Limerick, led by William Lee, has modelled bubble formation in stout beers in detail. Their work suggests that lining the rims of cans and bottles with a material similar to an ordinary coffee filter would be a simpler, cheaper alternative to the widget. The team’s calculations show that a copious number of bubbles would form from air trapped inside the hollow fibres making up this lining. They have just submitted their work for publication in Physical Review E and are hoping that industry will soon begin testing their proposal.