The case for the heterogeneous structure of glasses.

Since 1932, the structure of glasses and other amorphous solids has been taken to be homogeneously disordered (with the exception of a few researchers). However, recent developments in the low-temperature physics of glasses and amorphous films have strengthened the case for the ubiquitous heterogeneous intermediate-range structure made up of jam-packed solid-like frozen-in regions and liquid-like active regions in between. Evidence for this type of heterogeneity will be presented and the advantages of the refined structural model of glasses will be advocated for. In particular, evidence will be presented for a new type of paramagnetism due to the vitreous solid state itself. The theory for the magnetic effects in glasses based on this scenario bears the promise for much interesting new physics and a theory for the melting of glasses will be proposed.