localized but collective LEEs - P
LEEs - low-energy excitations - more general name than TLSs
- collective and universal
therefore quantum statistics!
collective game is qualitatively different from original individual game - microscopic origin is UNimportant if excitations are collective
- but localized
therefore different from delocalized critical modes around phase transitions
- QLTG - quantum low-temperature glasses
SNS is strongly noncrystalline solid
the definition of the consonance between glassons-fermions and phonons-bosons
phonon ($c_s$) parameters, fermion parameters ($m_{gl}$, Fermi velocity $v_F$, etc.), and their coupling $\lambda_{gl-ph}$ are self-consistent.
This structural consistency leads to universality of dimensionless sound friction $Q^{-1}$