Thermodynamics is the branch of physics that deals with the processes by which energy is transferred between entities. Its predictions are crucial to both chemistry and biology when determining whether certain chemical reactions or interconnected networks of reactions will proceed spontaneously. However, while thermodynamics tries to create a general description of macroscopic systems, we often encounter difficulties in working in the non-equilibrium system. Successful attempts to extend the framework to non-equilibrium situations have usually been limited to only specific systems and models. In two recently published studies, researchers from the Institute of Industrial Science at the University of Tokyo demonstrated that complex nonlinear chemical reaction processes could be described by transforming the problem into a geometric dual representation. “With our structure, we can extend the theories of nonequilibrium systems with quadratic diffusion functions to more general cases, which are important for the study of chemical reaction networks,” says first author Tetsuya J. Kobayashi. In physics, duality is a central concept. Some physical entities are easier to interpret when transformed into a different, but mathematically equivalent, representation. For example, a wave in time can be converted to its representation in frequency space, which is its dual form. When dealing with chemical processes, thermodynamic force and flux are the nonlinearly related dual representations — their product leads to the rate at which energy is lost in diffusion — in a geometric space induced by the duality, scientists were able to show how thermodynamic relations can be generalized even to non-equilibrium cases. “Most previous studies of chemical reaction networks have been based on assumptions about the kinetics of the system. We have shown how they can be handled more generally in the non-equilibrium case using duality and related geometry,” says last author Yuki Sughiyama. Having a more universal understanding of thermodynamic systems, and extending the application of non-equilibrium thermodynamics to more disciplines, can provide a better advantage for the analysis or design of complex reaction networks, such as those used in living organisms or industrial production processes. Story source: Materials provided by Institute of Industrial Science, University of Tokyo. Note: Content can be edited for style and length.
