Read articles, including Science News stories written for ages 9-14, on the SNK website.
Beer bubble math
A+ A- Text Size

 The rate of change of bubble volume. If this quantity is positive, the bubble will grow; if it’s negative, it will shrink. A constant that depends on the temperature and the specific gas in the foam. (The foam on top of a glass of Guinness lasts unusually long because Guinness uses nitrogen in addition to carbon dioxide in its beer. K is smaller for nitrogen, so the bubbles change size more slowly.) The sum of the lengths of the edges of the surfaces where the bubble intersects other bubbles. For an isolated bubble, E is 0; for a big bubble surrounded by many little bubbles, it is large. Any plane one can imagine that cuts through the bubble. The shape made by the intersection of plane P with the bubble. The Euler characteristic of the shape P ∩ B. The symbol for integrating over planes, which allows you to essentially add up the Euler characteristics of every possible way you might slice the bubble.
Comment

Please alert Science News to any inappropriate posts by clicking the REPORT SPAM link within the post. Comments will be reviewed before posting.

• nd how many taxpayer dollars did it cost us for this bit of worthless information? Who gives a damn? Some scientists need to find something else to do if this is all we can expect from them.
Prentice Price
Jun. 13, 2011 at 4:17pm
• That's how people reacted to the semiconductor..i.e., Why would anyone be interested in materials that neither conduct well or insulated well?
Frank Schieber
Jun. 13, 2011 at 4:42pm
• Gee Prentice. I am guessing that you are not a scientist. But I will bet that you use the computer that these hairbrained scientists came up with. And I will bet that you are on your cellphone that those same scientists developed when you drive. Try not to knock what scientists do if your vantage point does not give you the proper perspective. Maybe take a remedial science class.
HansSkyboy
Jun. 13, 2011 at 7:35pm
• Chances are, this equation is important in the manufacturing of foam-plastics and many other substances.
Pure science has brought us much amazing technology without knowing beforehand what use the information might be put to.
Greygoat
Jun. 14, 2011 at 10:46pm
• So, you're saying it's alright for a scientist to spend hunderdes of thousands of dollars to go out and study a pile of dog poo just because he or she might find a use for it someday? It doesn't take a scientist to figure out where it came from. It doesn't take a mathmatician to figure out where it's going. It doesn't take a PHD to know what to do with it. It does take a little common scense to relize some scince is a farce. If you don"t think so then i've got a pile of manure i'd love to sell in the name of sciencs.
Prentice Price
Jun. 15, 2011 at 7:09pm
• There is an implicit but unsupported assumption that discovering this equation cost vast sums of money.
There are further assumptions - on both sides - that the question is either irrelevant or valuable.
And there is a serious need for a spellchecker.
Tom
tom o'connor
Jun. 20, 2011 at 4:06pm
• Seems like something any self-respecting mathematician would work out on a napkin just for the fun of it. Much more interesting than the Sports or Entertainment sections, anyway.
James Dohleman
Aug. 1, 2011 at 9:58am
• That is fascinating that Guinness uses nitrogen! How cool that scientists understand the mathematical model for the bubble size and their duration. It may have interesting applications to understanding the "bends" which divers experience when they ascend rapidly to the ocean surface and bubbles form in their blood stream.
Aspen Logic
Jul. 10, 2012 at 9:22am