论文标题
准绝热参数变化的熵产生以流体动力为主
Entropy production for quasi-adiabatic parameter changes dominated by hydrodynamics
论文作者
论文摘要
实现多个颗粒系统绝热更改的典型策略是在时间尺度上慢慢改变参数，$ t_ \ text {r} $比内在平衡时间尺度大得多。在绝热状态准备的理想情况下，$ t_ \ text {r} \ to \ infty $，熵产生消失。在具有保护定律的系统中，由于流体动力波动的缓慢松弛而引起的流体动力学长期尾巴阻碍了绝热极限的方法。我们认为，在有限温度下，在一个或两个维度下的熵产生$ΔS$由流体动力模式控制，导致$ΔS\ sim 1/\ sqrt {t_ \ t_ \ text {r}} $ d = 1 $和$Δs\ sim \ sim \ ln（t t _ pexts） $ d = 2 $。在较高的维度中，熵产生由其他高能模式主导，$ΔS\ sim 1/t_ \ text {r} $。为了验证分析预测，我们在一个空间维度中模拟了具有点状颗粒的经典两组分气的非平衡动力学，并检查总熵产生作为$ t_ \ text {r} $的函数。
A typical strategy of realizing an adiabatic change of a many-particle system is to vary parameters very slowly on a time scale $t_\text{r}$ much larger than intrinsic equilibration time scales. In the ideal case of adiabatic state preparation, $t_\text{r} \to \infty$, the entropy production vanishes. In systems with conservation laws, the approach to the adiabatic limit is hampered by hydrodynamic long-time tails, arising from the algebraically slow relaxation of hydrodynamic fluctuations. We argue that the entropy production $ΔS$ of a diffusive system at finite temperature in one or two dimensions is governed by hydrodynamic modes resulting in $ΔS \sim 1/\sqrt{t_\text{r}}$ in $d=1$ and $ΔS \sim \ln(t_\text{r})/t_\text{r}$ in $d=2$. In higher dimensions, entropy production is instead dominated by other high-energy modes with $ΔS \sim 1/t_\text{r}$. In order to verify the analytic prediction, we simulate the non-equilibrium dynamics of a classical two-component gas with point-like particles in one spatial dimension and examine the total entropy production as a function of $t_\text{r}$.
