Much the same way Cheerios collect together while floating in milk or toothpicks align while floating in water, particles on the molecular level will self-organize – a process driven by mutual attraction and friction.
A general mathematical description of friction among particles in gasses, fluids and plasmas has eluded researchers for some time. Recent research published in the French Academy of Sciences (Comptes Rendus de l’Academie des Sciences) co-authored by Vakhtang Putkaradze, associate professor of mathematics at Colorado State University, outlines a new approach for modeling the geometric dissipation of kinetic equations.
Putkaradze partnered with mathematics professor Darryl Holm and graduate student Cesare Tronci of London’s Imperial College on the report. Holm is a fellow at the Los Alamos National Laboratory, a U.S. Department of Energy facility where he worked for more than three decades.
"When you push something, it forms resistance proportional to velocity," Putkaradze said. "All this work is about what is ‘force’ and what is ‘velocity.’"
The research is part of a greater understanding of particle interaction with potential applications in nanosensor science, a field that has the potential to delivering fast but tiny computers and sensor capable of detecting minute amounts of molecules that would have military applications.
Previous mathematical models have been limited to portraying simple-shaped round molecules. However, many molecules have more complex shapes. The research team sought to model basic principles that underlie how molecules come together and how geometry affects the process. The research can model molecules lining up in strands.
"You can put these molecules in a line; then you can build a much better sensor," Putkaradze said. "Energy dissipation ensures that molecules end up in certain spots."
The potential sensors would be thinner than a human hair, but could be used to detect minute particles. In military use, this could include detecting traces of bomb-making compounds that are undetectable with current equipment.