Fig. 6: Relaxation map highlighting the unexplored regime of long-term glass aging.

For relaxation times shorter than one year, both equilibrium and non-equilibrium states of glass can be experimentally accessed and characterized by fast relaxation modes such as α, β, and β′. However, in the non-equilibrium regime where the relaxation time exceeds one year, experimental data are extremely scarce and existing theoretical models fail to provide accurate descriptions, resulting in a “no man’s land” in the study of long-term glass aging. The image of lunar glasses is reproduced from Ref. ¹³ under a CC BY-NC license.