Who would have thought that soap bubbles would generate
so much media attention in the 20th and 21st century?
It isn't as
though bubbles are a new phenomena but somehow writers in countries
throughout the world have been delighted when they found that this
subject can carry their readers into the highest realms of mathematics,
physics and archetecture as well as the kitchens, bathtubs, playgrounds,
classrooms and street corners of the world.
Word New Scientist magazine
January 17, 2004
Q: Is it possible to blow a toroidal soap bubble (one shaped like a
ring doughnut)? And if it is, would it collapse immediately to a sphere?
Could its life be prolonged by spinning its surface, as with smoke rings?
A: As a mathematician who studies soap bubbles, I knew that a toroidal
soap bubble was "impossible." The only stable equilibrium shape for a soap
bubble is a round sphere, and a torus bubble is not even in unstable equilibrium.
So when the famous performer Tom Noddy (the "Bubble Guy" of Tonight Show
fame) told me he once blew a toroidal bubble, I could hardly believe him
until he showed me the photo. But that bubble didn't last long, and I don't
think spinning would help much. Visit www.tomnoddy.com/science.html to
see some further interesting examples of soap bubble shapes.
Incidentally, torus bubbles do occur in unstable equilibrium in double soap
bubbles, wrapped around another bubble at the center,
as in the computer simulation created by John M. Sullivan, professor of mathematics
at the University of Illinois. More of his images are online at http://torus.math.uiuc.edu/jms/images/