First-principle determination of landscape and the unifying concept for glass transition

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1.A unifying concept for understanding glass transition was found on the basis of the free energy landscape which plays the same role as the free energy in the Landau theory of phase transitions.2.A novel method to calculate the free energy landscape was found using the density functional of the grand potential. Analyzing the free energy landscape obtained, we showed that the string motion is a common elementary process of the slow relaxation and that there are two kinds of the cooperatively rearranging regions.3.The principal component analysis was utilized to calculate the free energy landscape from the molecular simulation data.4.An interactive molecular dynamics simulation and a fast method to construct the Voronoi tessellation were developed. These methods were exploited to calculate the temperature dependence of the cooperatively rearranging region.5.Using a microscopic theory we showed that the jump rate distribution obeys a power law function.6.The temperature dependence of the specific heat of a model glass former was obtained within the frame work of the free energy landscape and it was shown that the cooling rate dependence of the glass transition can be explained by the landscape picture.7.On the basis of the free energy landscape picture, the first and second order frequency-dependent (complex) specific heats were defined and their anomalous behavior was found around the glass transition point and the Vogel-Fulcher temperature.8.Packing fraction of binary hard discs was obtained in the entire parameter space and it was found that the packing fraction has a minimum as a function of the ratio of radii.