arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0705.2688cond-mat.stat-mechcond-mat.soft
收藏

颗粒流体中爱因斯坦关系的破坏:相关性的作用

Violation of the Einstein relation in Granular Fluids: the role of correlations

A. Puglisi, A. Baldassarri, A. Vulpiani

摘要:

我们研究了不同驱动颗粒气体模型中的线性响应。在某些情况下,即使速度统计可以是强非高斯的,我们也没有观察到明显违反爱因斯坦公式的扩散与迁移率。当速度和密度之间存在强相关性时,情况发生了变化:在这种情况下,尽管存在一种形式的波动耗散关系,但粒子的微分速度响应及其速度自相关性不再成比例。这发生在高密度和强非弹性,但仍然在流体状(和遍历)制度。

英文摘要:

We study the linear response in different models of driven granular gases. In some situations, even if the the velocity statistics can be strongly non-Gaussian, we do not observe appreciable violations of the Einstein formula for diffusion versus mobility. The situation changes when strong correlations between velocities and density are present: in this case, although a form of fluctuation-dissipation relation holds, the differential velocity response of a particle and its velocity self-correlation are no more proportional. This happens at high densities and strong inelasticities, but still in the fluid-like (and ergodic) regime.

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。

↑