A density scaling conjecture for aging glasses.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Physical Chemistry

Background:

• Traditional models for aging glasses primarily use temperature and fictive temperature, omitting density.
• This approach lacks connection to equilibrium relaxation rates, which are known to depend on both temperature and density.
• Many systems exhibit density scaling, where relaxation rates depend on a scaling parameter Γ = e(ρ)/T.

Purpose of the Study:

• To generalize the concept of fictive temperature for aging glasses.
• To propose a density scaling conjecture for aging glasses.
• To incorporate density as a key parameter in modeling glass aging rates.

Main Methods:

• Generalizing the fictive temperature concept to a fictive scaling parameter (Γ_fic).
• Developing a density scaling conjecture for aging glasses.
• Analyzing the dependence of aging rate on density scaling parameter (Γ) and fictive scaling parameter (Γ_fic).

Main Results:

• A generalized fictive scaling parameter (Γ_fic) is proposed.
• A density scaling conjecture is introduced for aging glasses.
• The aging rate is shown to depend on both Γ and Γ_fic.

Conclusions:

• The proposed model offers a more comprehensive understanding of glass aging dynamics.
• Incorporating density provides a more physically grounded approach to modeling relaxation rates.
• This work bridges the gap between equilibrium and non-equilibrium descriptions of glass behavior.