arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0808.4160cond-mat.stat-mechcs.ITmath.ITmath.PRphysics.data-an
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利用相对熵求最佳近似:在简单流体中的应用

Using Relative Entropy to Find Optimal Approximations: an Application to Simple Fluids

Chih-Yuan Tseng, Ariel Caticha

摘要:

我们开发了最大相对熵形式主义来生成概率分布的最佳逼近。主要结果包括:(a)证明使用相对熵作为唯一自然的标准,以选择一个首选的近似从一个家庭内的试验参数化分布,和(b)获得最佳的近似边缘化的参数使用最大熵和信息几何的方法。作为一个例子,我们将我们的方法应用到简单的流体。“精确”的正则分布近似的硬球流体。所提出的方法首先确定硬球直径的优选值,然后通过在不同硬球直径上的适当加权平均来获得最佳硬球近似。这导致了一个相当大的改善占软核性质的原子间的潜力。作为一个数值演示,径向分布函数和状态方程的Lennard-Jones流体(氩)进行了比较,从分子动力学模拟的结果。

英文摘要:

We develop a maximum relative entropy formalism to generate optimal approximations to probability distributions. The central results consist in (a) justifying the use of relative entropy as the uniquely natural criterion to select a preferred approximation from within a family of trial parameterized distributions, and (b) to obtain the optimal approximation by marginalizing over parameters using the method of maximum entropy and information geometry. As an illustration we apply our method to simple fluids. The "exact" canonical distribution is approximated by that of a fluid of hard spheres. The proposed method first determines the preferred value of the hard-sphere diameter, and then obtains an optimal hard-sphere approximation by a suitably weighed average over different hard-sphere diameters. This leads to a considerable improvement in accounting for the soft-core nature of the interatomic potential. As a numerical demonstration, the radial distribution function and the equation of state for a Lennard-Jones fluid (argon) are compared with results from molecular dynamics simulations.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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