The dynamics of fluid-filled Tibetan bowls was the research subject of Denis Terwagne during his internship in the Applied Math Lab. Our combined experimental and theoretical investigation elucidated the manner in which the rubbing of the bowl excites its resonant wave modes, which in turn excite Faraday waves on the fluid surface that may break, giving rise to the ejection of droplets that bounce in place or skip across the free surface.
See paper here: Terwagne & Bush (2011)
“And he showed Pierre a globe, a quivering ball of no dimensions, its surface consisting of drops tightly packed together. The drops moved and shifted, now merging from several into one, now dividing from one into many. Each drop strove to spread and take up the most space, but the others, striving to do the same, pressed against it, sometimes destroying, sometimes merging. “This is life”, said the old teacher. “In the center is God, and each drop strives to expand in order to reflect Him in the greatest measure. It grows, merges and shrinks, is obliterated on the surface, vanishes into the depths, then resurfaces.”
– Leo Tolstoy, War and Peace, 1865