OK, perhaps it's only on a microscopic level and requires low pressure, however it's a step in the perpetual motion direction!
The article begins:
- The behavior of very small things can surprise humans, who are used to living in a world of their own size, dominated by gravity.
It takes a lot of energy for humans to leave the ground — very strong legs for short leaps, and rocket engines for big ones.
So imagine not only rising, but also bouncing higher when one falls back to earth, and higher again the next time. It can be done on a trampoline, of course.But researchers in Switzerland found that microscopic droplets on a surface that is super water repellent can be made to spontaneously launch themselves upward and then bounce even higher after they fall to the surface again.
The surface they were working with is rigid like the ground or a tabletop, and not bouncy like a trampoline, so videos of the droplets look like pure levitation.
What drives the bouncing droplet phenomenon is a lowering of atmospheric pressure that increases evaporation, according to the researchers, who published their findings in the journal Nature: