Absorption and dispersion of electromagnetic eigenwaves of electron-positron plasma in a strong magnetic field: H. Pérez Rojas and A. E. Shabad. Instituto de Investigación Técnica Fundamental,Havana, Cuba

Quantum theories of N-component Fermi fields are formulated in terms of overcomplete sets of bilocal pseudo-spin operators in analogy with the Holstein-Primakoff theory of ordinary spin systems. Classical constrained Hamiltonian systems arise in the large N limit revealing the semi-classical nature of the large N approximation. Such systems are briefly analyzed in the context of the Gross-Neveu $\text{(}\text{ψ}\text{ψ)}{}^2$ model, where the dynamics of c-number (rather than Grassman) fields governs the semi-classical limit.