Glasses under high pressure: a link to colloidal science?

Whether glass formation is mainly driven by temperature or by pressure is an open question that is now being addressed in high-pressure experiments. Here we propose that some insight into these questions could be gained by comparing in a suitable manner with colloidal glass-transition data. Based on such a comparison, a cross-over is found from the usual regime of molecular glasses (where temperature effects tend to be important) to a very-high-pressure regime (where density effects eventually take over). This regime is found to be located at pressures higher than commonly studied in today's glass-transition experiments.