Soap bubbles are physical examples of the complex mathematical problem of minimal surface.
While it has been known since 1884 that a spherical soap bubble is the least-area way of enclosing a given volume of air (a theorem of H. A. Schwarz), it was not until 2000 that it was proven that two merged soap bubbles provide the optimum way of enclosing two given volumes of air of different size with the least surface area.
The structures that soap films make can not just be enclosed as spheres, but virtually any shape, for example in wire frames.
It is thus sensitive to : After experiments, researchers found that a solution containing: gave the longest lasting results as it minimised the Marangoni Effect.
& F. Pears created a famous advertising campaign for its soaps in 1886 using a painting by John Everett Millais of a child playing with bubbles.
Dishwashing liquid with water and additional ingredients such as glycerin and sugar is used as a popular alternative to a ready made bubble solution.
However, the soap film is as thin as the visible light wavelength, resulting in optical interference.
This creates iridescence which, together with the bubble's spherical shape and fragility, contributes to its magical effect on children and adults alike.
Tom Noddy (who featured in the second episode of Marcus du Sautoy's The Code) gave the analogy of looking at a contour map of the bubbles' surface.
In 2010, Japanese astronaut Naoko Yamazaki demonstrated that it is possible to create coloured bubbles in microgravity.
A bubble, created successfully at this low temperature, will always be rather small; it will freeze quickly and will shatter if increased further.
[13] Freezing of small soap bubbles happens within 2 seconds after setting on snow (at air temperature around –10...–14 °C).
[citation needed] Some performers use common commercially available bubble liquids while others compose their own solutions.
Some artists create giant bubbles or tubes, often enveloping objects or even humans.
To add to the visual experience, they are sometimes filled with smoke, vapour or helium and combined with laser lights or fire.
Bubbles can be effectively used to teach and explore a wide variety of concepts to even young children.
Flexibility, colour formation, reflective or mirrored surfaces, concave and convex surfaces, transparency, a variety of shapes (circle, square, triangle, sphere, cube, tetrahedron, hexagon), elastic properties, and comparative sizing, as well as the more esoteric properties of bubbles listed on this page.
A Swiss university professor, Dr. Natalie Hartzell, has theorized that the usage of artificial bubbles for entertainment purposes of young children has shown a positive effect in the region of the child's brain that controls motor skills and is responsible for coordination with children exposed to bubbles at a young age showing measurably better motion skills than those who were not.