论文标题
最佳电流的熵生产估算
Entropy production estimation with optimal current
论文作者
论文摘要
熵产生表征了热力学不可逆性,并反映了散发到环境中的热量,并且在非平衡系统中损失的自由能量。根据热力学不确定性关系,我们提出了一种确定性方法,以估算系统状态的单个轨迹的熵产生。我们明确并大致计算了最佳电流,该电流使用预定的基线产生最紧密的下限。值得注意的是,获得的最紧密的下限与多维热力学不确定性关系密切相关。通过证明热力学不确定性关系在短时限制中的饱和度,对于过度引导的Langevin Systems,可以获得熵产生的确切估计,而与基本动力学无关。对于马尔可夫跳跃过程,因为没有理论上确保热力学不确定性关系的可达到性,因此提出的方法为熵产生提供了最紧密的下限。当熵产生是最佳电流时,可以使用积分波动定理进一步获得更准确的估计值。我们使用三个系统说明了提出的方法:四州马尔可夫链,一个定期驱动的粒子和多个珠子弹簧模型。估计的结果在所有示例中的结果都凭经验验证了所提出的方法的有效性和效率。
Entropy production characterizes the thermodynamic irreversibility and reflects the amount of heat dissipated into the environment and free energy lost in nonequilibrium systems. According to the thermodynamic uncertainty relation, we propose a deterministic method to estimate the entropy production from a single trajectory of system states. We explicitly and approximately compute an optimal current that yields the tightest lower bound using predetermined basis currents. Notably, the obtained tightest lower bound is intimately related to the multidimensional thermodynamic uncertainty relation. By proving the saturation of the thermodynamic uncertainty relation in the short-time limit, the exact estimate of the entropy production can be obtained for overdamped Langevin systems, irrespective of the underlying dynamics. For Markov jump processes, because the attainability of the thermodynamic uncertainty relation is not theoretically ensured, the proposed method provides the tightest lower bound for the entropy production. When entropy production is the optimal current, a more accurate estimate can be further obtained using the integral fluctuation theorem. We illustrate the proposed method using three systems: a four-state Markov chain, a periodically driven particle, and a multiple bead-spring model. The estimated results in all examples empirically verify the effectiveness and efficiency of the proposed method.