具有许多隐藏变量的微观热机
A microscopic heat engine with many hidden variables
- Science Division, West Los Angeles College（西洛杉矶学院科学部）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本文通过秩一耦合结构揭示微观热机失速时隐藏电流与熵产生的精确关系，指出正交隐藏电流的耗散不可由机械通道推断。
AI中文摘要：
微观马达通常通过单一机械坐标进行监测，而维持其运动的化学、构象或旋转循环仍未被解析。机械失速由平均观测速度的消失来定义；然而，这一标量条件通常并不蕴含热力学可逆性。我们分析了一个过阻尼布朗马达，其中观测坐标通过单个共享相互作用势与多个内部相位耦合。由于传递的力和反作用力矩源自同一能量，所得到的秩一互易结构在观测概率流和隐藏概率流之间产生精确的点态恒等式。该恒等式为任意周期性相互作用在失速时的熵产生提供了精确表达式。特别地，机械通道中的正电流平方耗散，由完整稳态通过耦合坐标分辨的局部速度定义，与失速载荷一起决定了投影到耦合方向上的集体隐藏电流。然而，稳态的一坐标边缘电流在失速时恒等地消失；因此，稳态边缘密度和平均位移电流不能确定该耗散。正交于耦合方向的隐藏电流在不影响观测运动的情况下耗散，并产生一个不可约贡献，该贡献无法从秩一机械通道推断出来。
英文摘要：
Microscopic motors are commonly monitored through a single mechanical coordinate, whereas the chemical, conformational, or rotational cycles that sustain their motion remain unresolved. Mechanical stall is defined by the vanishing of the mean observed velocity; this scalar condition, however, does not generally imply thermodynamic reversibility. We analyze an overdamped Brownian motor in which one observed coordinate is coupled to several internal phases through a single shared interaction potential. Because the transmitted force and the reaction torques derive from the same energy, the resulting rank-one reciprocal structure yields an exact pointwise identity between the observed and hidden probability currents. This identity provides an exact expression for the entropy production at stall for an arbitrary periodic interaction. In particular, a positive current-square dissipation in the mechanical channel, defined from the full stationary state through the coupling-coordinate-resolved local velocity, determines together with the stall load the collective hidden current projected onto the coupling direction. The stationary one-coordinate marginal current nevertheless vanishes identically at stall; consequently, the stationary marginal density and mean displacement current do not determine this dissipation. Hidden currents orthogonal to the coupling direction dissipate without affecting the observed motion and generate an irreducible contribution that cannot be inferred from the rank-one mechanical channel.
