  We study the interplay between the fluid-crystal transition and the glass
transition of elastic sphere system with polydispersity using nonequilibrium
molecular dynamics simulations. It is found that the end point of the
crystal-fluid transition line, which corresponds to the critical polydispersity
above which the crystal state is unstable, is on the glass transition line.
This means that crystal and fluid states at the melting point becomes less
distinguishable as polydispersity increases and finally they become identical
state, i.e., marginal glass state, at critical polydispersity.
