Out-of-equilibrium chemical networks: dissipation shapes selection

Life has most likely originated as a consequence of processes taking place in non-equilibrium conditions (e.g. in the proximity of deep-sea vents) selecting states that would have been otherwise unfavorable at equilibrium. Here we present a simple chemical network in which the selection of states is driven by the dissipation rate, as previously suggested in the literature: states participating to faster reactions dissipate faster and are the most populated ones in non-equilibrium steady-state conditions. Building upon these results, we show that, as the complexity of the chemical network increases, the velocity of the reaction path leading to a given state determines its selection, giving rise to phenomena of global localization in state space. A byproduct of our studies is that, in the presence of a temperature gradient, thermophoresis-like behavior inevitably appears depending on the transport properties of each individual state, thus hinting at a possible microscopic explanation of this intriguing and long-standing phenomenon.