14 DAY TRIAL // Entropy is a concept that is usually utilized as a measure of disorder within a system. When looking into its definition more closely, it's revealed that it actually refers to the number of random ways a system can develop in, given enough time. The idea is widely used in thermodynamics and statistical mechanics, as well as in the field of astronomy, to explain the state of the Universe. A number of scientists has proposed in recent years the idea that entropy may actually be promoting the development of ordered structures, but the belief has been refuted. Now, experts return with more proof.
Experts from the University of Michigan have demonstrated in a new series of experiments that entropy alone can allow for pyramid shapes to spontaneously organize into complex quasicrystals. The latter are solid materials with some amazing characteristics, including the fact that none of their patterns or single units repeats itself, and the ability to display long-range order. The science group published its findings in the December 10 issue of the top scientific journal Nature. Also involved in the investigation were experts from the Case Western Reserve University, and the Kent State University.
For the work, the team used a tetrahedron, a three-dimensional, four-faced, triangular polyhedron, which is widely employed in biology and nanotechnology research. “Tetrahedrons are the simplest regular solids, while quasicrystals are among the most complex and beautiful structures in nature. It's astonishing and totally unexpected that entropy alone can produce this level of complexity,” UM expert Sharon Glotzer says. She is the principal investigator of the new work, as well as a professor in the departments of Chemical Engineering and Materials Science and Engineering at UM.
The research also revealed a new solution to a very complex mathematical problem, which refers to packing as many objects inside a box as tightly as possible. Last year saw an expert breaking the previous record, but the new investigation breaks last year's record, by reaching the densest achievable packing of tetrahedrons, the group says. “Our results go to the very heart of phase transitions and to the question of how complex order arises in nature and in the materials we make. We knew that entropy on its own could produce order, but we didn't expect it to produce such intricate order. What else might be possible just due to entropy?” Glotzer shares.