The notion of quantum group replaces ordinary matrices with matrices with non-commutative elements. This notion is physically very interesting, and in TGD framework I have proposed that it should relate to the inclusions of von Neumann algebras allowing to describe mathematically the notion of finite measurement resolution (see this). These ideas have developed slowly through various side tracks.
In it is interesting to consider the notion of quantum matrix inspired by recent view about quantum TGD. It turns out that under some additional conditions this approach provides a concrete representation and physical interpretation of quantum groups in terms of finite measurement resolution.
Quantum matrices define a more general structure than quantum group but provide a concrete representation for them in terms of finite measurement resolution if q is a root of unity. For q=+/- 1 (Bose-Einstein or Fermi-Dirac statistics) one obtains quantum matrices for which the determinant is apart from possible change by sign factor invariant under the permutations of both rows and columns. One can also understand the recursive fractal structure of inclusion sequences of hyper-finite factors resulting by replacing operators appearing as matrix elements with quantum matrices and a concrete connection with quantum groups emerges.
In Zero Energy Ontology (ZEO) M-matrix serving as the basic building brick of unitary U-matrix and identified as a hermitian square root of density matrix provides a possible application for this vision. Especially fascinating is the possibility of hierarchies of measurement resolutions represented as inclusion sequences realized as recursive construction of M-matrices. Quantization would emerge already at the level of complex numbers appearing as M-matrix elements.
This approach might allow to unify various ideas behind TGD. For instance, Yangian algebras emerging naturally in twistor approach are examples of quantum algebras. The hierarchy of Planck constants should have a close relationship with inclusions and fractal hierarchy of sub-algebras of super-symplectic and other conformal algebras.
See the article Analogs of quantum matrix groups from finite measurement resolution? or the chapter Evolution of Ideas about Hyper-finite Factors in TGD.