 Fortunately, for various phenomena it is legitimate to neglect the postulates of SRT, namely when the relevant velocities are small in relation to the speed of light and when the kinetic energies of the particles are small compared to their mass energies \(mc^2\). And this is the reason why non-relativistic QM, although it cannot be the correct theory in the end, has its empirical successes. But it can never be the appropriate framework for electromagnetic phenomena because electrodynamics, which prominently encompasses a description of the behavior of light, is already relativistically invariant and therefore incompatible with non-relativistic QM. Relativistic scattering experiments are another context in which QM fails. Since the involved particles often travel close to the speed of light, relativistic effects can no longer be neglected. For that reason high-energy scattering experiments can only be correctly confronted by QFT.