Heart of glass

The deceived wisdom that glass is a very slow-moving liquid has persisted for many years. Finally, researchers at the University of Bristol in the UK and the University of Kyoto, Japan, have combined computer simulation and information theory, to show that silica glass is in fact solid. When looked at under the microscope, it appears glass never truly solidifies but keeps flowing, albeit extremely slowly -- so slowly, in fact, that it would take over 10 million years for a window pane to flow perceptibly, despite that deceived wisdom about medieval window panes being thicker at the bottom! "We found that the size of the solid regions of icosahedra would grow until eventually there would be no more liquid regions and so the glass should be a true solid," explains team member Paddy Royall.