2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/51090Based on experimental discovery that the mass-square of neutrino is negative, a quantum equation for superluminal neutrino is proposed in comparison with Dirac equation and Dirac equation with imaginary mass. A virtual particle may also be viewed as superluminal one. Both the basic symmetry of space-time inversion and the maximum violation of space-inversion symmetry are emphasized.6 pages, LatexHigh Energy Physics - Theorytext