Non-trivial roles of multi-particle correlations in fragile glass formers

It is widely believed that the emergence of slow glassy dynamics is encoded in a material's microstructure. For fragile glass formers such as the archetypical hard-sphere model, the static structure factor, i.e., the static two-point density correlation, is usually assumed to be sufficient to describe all relevant structural features that give rise to glassy dynamics. We challenge this status quo by studying a binary hard-sphere mixture with a first-principles-based theory that can systematically take higher-order static and dynamic correlations into account. We find that only including the static triplet direct correlations already changes the prediction of the glass-transition diagram both qualitatively and quantitatively. The diagram is also tremendously affected by increasing the order of the dynamic multi-point density correlations in the theory. Hence, even for simple fragile materials, the conventionally neglected static triplet direct correlations as well as the higher order static and dynamic correlations are in fact non-negligible.