The Higgs mechanism for undergraduate students

The Higgs mechanism gives mass to particles as a result of the interaction between massless particles and a scalar field. In this version it is reformulated in a purely classical form, using a simple formalism suitable for undergraduate students. The need for the Higgs field is justified with arguments following from a review of the concept of energy and from special relativity. While most of the popularisations of the Higgs mechanism relies on analogies with friction, the proposed explanation appears to be at the same time formally coherent and simple enough to be proposed to undergraduate students, the prerequisites being just the knowledge of the energy density of electric and magnetic fields.