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"OH WATERS, TEEM WITH MEDICINE TO KEEP MY BODY SAFE FROM HARM, SO THAT I MAY LONG SEE THE SUN." - Rig Veda
Keep a close eye on the bead using a video camera and every time you see it go up a step, change the electric field so that it cannot drop back down again. This is like placing a barrier behind the bead.
This is exactly the experiment that Shoichi Toyabe at Chuo University in Tokyo and a few buddies have successfully carried out. The implication is that the bead is somehow able to extract energy from the environment, which at first sight, looks like a blatant violation of the 2nd law of thermodynamics .
Of course, there's more to this than first appears. Toyabe and co's work is an experimental version of the famous Maxwell's demon. Imagine a box filled with air but divided in half by a barrier. Maxwell's demon is an imaginary being capable of opening the barrier to allow fast moving molecules through while closing it for slower ones.
The most recent thinking is that Maxwell's demon does not violate the 2nd law of thermodynamics because it has to measure the velocity of all the molecules before deciding which to let through and this requires energy. When this is taken into account, there is no violation.
But here's the curious thing. There is no conventional transfer of energy into the system: no heating or accelerating of molecules or some such. Instead, information itself seems to be the medium through which energy is transferred.
That kind of thinking has been a theoretical curiosity, until now. Toyabe and friends' have actually done it, the first experimental demonstration of this kind of energy transmission. In effect they've converted information into energy in this system.
There's no violation of thermodynamics here. These guys use a video camera to determine the position of the bead so when the camera's energy budget is taken into account, everything works out as the laws of thermodynamics predict.