Microscopic aspects of Stretched Exponential Relaxation (SER) in homogeneous molecular and network glasses and polymers

► Glassy stretched exponential relaxation is the oldest unsolved problem in science. ► The curated data base bifurcates into two “magic” exponents β1 = 3/5 and β2 = 3/7. ► Diffusion to traps derives β1 from short hops, β2 from mixed short/long hops. ► Elastic relaxation can be used for quality control. ► 600 million 20th century citations bifurcated into β1 = 3/5, 3/7 (<, > 1960).