In many complex systems, whether biological or artificial, the thermodynamic costs of communication among their components are large. These systems also tend to split information transmitted between any two components across multiple channels. A common hypothesis is that such inverse multiplexing strategies reduce total thermodynamic costs. So far, however, there have been no physics-based results supporting this hypothesis. This gap existed partially because we have lacked a theoretical framework that addresses the interplay of thermodynamics and information in off-equilibrium systems at any spatiotemporal scale. Here we present the first study that rigorously combines such a framework, stochastic thermodynamics, with Shannon information theory. We develop a minimal model that captures the fundamental features common to a wide variety of communication systems. We find that the thermodynamic cost in this model is a convex function of the channel capacity, the canonical measure of the communication capability of a channel. We also find that this function is not always monotonic, in contrast to previous results not derived from first principles physics. These results clarify when and how to split a single communication stream across multiple channels. In particular, we present Pareto fronts that reveal the trade-off between thermodynamic costs and channel capacity when inverse multiplexing. Due to the generality of our model, our findings could help explain empirical observations of how thermodynamic costs of information transmission make inverse multiplexing energetically favorable in many real-world communication systems.

翻译：在许多复杂系统中，无论是生物系统还是人工系统，其组件间通信的热力学代价都相当庞大。这些系统还倾向于将任意两个组件之间传输的信息分割到多个通道中。一个常见的假设是，这种逆多路复用策略能够降低总热力学代价。然而，迄今为止，尚无基于物理学的成果支持这一假设。这一空白部分源于我们缺乏一个理论框架来探讨任何时空尺度下非平衡系统中热力学与信息之间的相互作用。本文首次提出了一项研究，严格将随机热力学这一理论框架与香农信息论相结合。我们建立了一个最小模型，该模型捕捉了广泛通信系统共有的基本特征。我们发现，该模型中的热力学代价是信道容量（即衡量信道通信能力的标准量度）的凸函数。我们还发现，与先前并非基于第一性原理物理学的结论不同，该函数并非总是单调的。这些结果阐明了何时以及如何将单一通信流分割到多个通道中。特别是，我们提出了帕累托前沿，揭示了逆多路复用过程中热力学代价与信道容量之间的权衡关系。由于我们的模型具有普遍性，研究结果有助于解释实证观察结果，即信息传输的热力学代价如何使逆多路复用在许多实际通信系统中在能量上更有利。