In this work, we revisit the description of dynamics based on the concepts of metabasins and activation in mildly supercooled liquids via the analysis of the dynamics of a paradigmatic glass former between its onset temperature \(T_{\mathrm{o}}\) and mode-coupling temperature \(T_{\mathrm{c}}\). First, we provide measures that demonstrate that the onset of glassiness is indeed connected to the landscape, and that metabasin waiting time distributions are so broad that the system can remain stuck in a metabasin for times that exceed \(\tau _{\alpha }\) by orders of magnitude. We then reanalyze the transitions between metabasins, providing several indications that the standard picture of activated dynamics in terms of traps does not hold in this regime. Instead, we propose that here activation is principally driven by entropic instead of energetic barriers. In particular, we illustrate that activation is not controlled by the hopping of high energetic barriers and should more properly be interpreted as the entropic selection of nearly barrierless but rare pathways connecting metabasins on the landscape.

在这项工作中，我们通过分析典型玻璃形成体在起始温度\(T_{\mathrm{o}}\)和模式耦合温度\(T_{\mathrm{c}}\) 。首先，我们提供了一些措施来证明玻璃化的开始确实与景观有关，并且元盆地等待时间分布非常广泛，以至于系统可以在超过\(\tau _{\alpha }的时间内停留在元盆地中。 \)的数量级。然后，我们重新分析了元盆地之间的转变，提供了一些迹象表明，陷阱方面的激活动力学的标准图在这种情况下并不成立。相反，我们建议这里的激活主要是由熵而不是能量障碍驱动的。特别是，我们说明激活不是由高能障碍的跳跃控制的，更正确地应该解释为连接景观上的元盆地的几乎无障碍但罕见的路径的熵选择。