I have always wondered if the equations of quantum field theory were actually ever used in the production of some invention or device other than needed to make predictions about the Standard Model of Particle physics of which quantum field theory was actually necessary in order to complete the Standard Model.
Perhaps the development of radio, television, MRI or possibly all the advances in the construction of nuclear power plants. I know Einsteins's field equations of General Relativity come in handy in GPS systems and quantum mechanics was needed to develop the transistor and the vast explosion in micro processors, superconductors, and solid state devices.
Is quantum field theory a set of equations used as a guide line when these inventions are created or is this some other finely tuned set of equations used only by the theoretical elite. I am not sure where to post the question since this isn't a specific question about a historical date but someone versed in history of scientific inventions might like to comment.