The Classical (Non-quantized) EM Field

Electrons, photons, atoms, and other quantum objects are made of the quantized energy of physical fields. As essential background for understanding quantum fields, this chapter discusses the non-quantized or “classical” EM field, including Young's 2-slit experiment, Maxwell's equations, and EM waves. Although Maxwell and others thought the medium that supports EM waves to be a material “ether,” this medium is non-material and “relativistic.” It is simply the universal EM field itself. This field plays a unique role in the history of QP because its classical aspects were known long before the discovery of quantization, yet it survives as one of the 25 universal fields of QP's Standard Model. This chapter studies this field's classical aspects including the reality of EM fields and waves, and the energy of the EM field. This leads to a comparison of realism and “idealism,” and concludes that realism is by far the more useful of these two philosophical worldviews. The criterion for reality is energy: A thing is real if and only if it has energy.