2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/25020We study the time reversal and space inversion symmetry properties of those transfer matrices mostly used in the calculation of energy spectra and transport-process. We study the time reversal and space inversion symmetry properties of those transfer matrices mostly used in the calculation of energy spectra and transport-process quantities. We determine the unitary transformation relating transfer matrices. We consider the Kohn-Luttinger model for a quasi-2D system and show that even though the system studied in the (4 x 4) scheme satisfies all the symmetry requirements, the (2 x 2)subspaces do not fulfill such constrains, except in the Gamma point of the Brillouin Zone. We find new exchange properties between the (2\times 2)subspace quantities.12 pages, none figuresMesoscale and Nanoscale PhysicsOther Condensed MatterMathematical PhysicsSymmetries and General Principies in the Multiband Effective Mass Theory: A Transfer Matrix Studytext