Since the end of the 19th century, physicists have known that the transfer of energy from one body to another is associated with entropy. It quickly became clear that this quantity is of fundamental importance, and so began its triumphant rise as a useful theoretical quantity in physics, chemistry and engineering. However, it is often very difficult to measure. Professor Dietmar Block and Frank Wieben of Kiel University (CAU) have now succeeded in measuring entropy in complex plasmas, as they reported recently in the renowned scientific journal Physical Review Letters. In a system of charged microparticles within this ionized gas, the researchers were able to measure all positions and velocities of the particles simultaneously. In this way, they were able to determine the entropy, as it was already described theoretically by the physicist Ludwig Boltzmann around 1880.
Click here for original story, Physicists determine the barely-measurable property entropy for the first time in complex plasmas
Source: Phys.org