What is what we call the ‘quantum field’? Answering from a teaching perspective by taking the foundations into account

Within physics education research a number of teaching proposals aimed at introducing elements of particle physics into secondary-school and introductory-university-level courses have been produced in recent years. Many of them face the problem of introducing the notion of the quantum field, which has a central role in contemporary physics. In this paper two representative examples are discussed; it is shown that both of them take the standard approach to introducing quantum field theory at university level (the ‘canonical quantization approach’) as their reference and that at the same time they introduce some ideas regarding quantum fields that are problematic when recent studies of the foundations of quantum field theory are taken into account. Starting from recent reformulations of quantum field theory, a different perspective to the notion of the quantum field is presented and a certain number of original insights that seem to be promising from a teaching perspective are emphasized