fragilityMin
plain-language theorem explainer
The definition assigns 16 as the lower bound on the fragility index for strong glasses such as SiO2. Glass transition researchers cite this constant when classifying materials by viscosity increase near Tg under RS 8-tick dynamics. The assignment is a direct numerical constant with no computation or lemmas.
Claim. The lower bound on the fragility index is $16$.
background
The module treats glass transition via 8-tick relaxation dynamics, where fragility measures departure from Arrhenius viscosity near Tg. Strong glasses (SiO2-like) exhibit low fragility while fragile glasses (polymers) show high values. The upstream fragility definition supplies the dimensionless proxy fragility(k) = (1/φ)^{8(k+1)}, decaying universally with the eight-beat period drawn from the T7 octave in the forcing chain.
proof idea
Direct constant definition with no lemmas applied.
why it matters
This constant supplies the lower threshold for the isStrongGlass predicate, which classifies materials with fragility between 16 and 30 as strong glasses. It implements the RS prediction that strong glasses correspond to low fragility tied to 8-tick relaxation and φ-scaling. The definition closes the classification interface for the glass transition module.
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