The field is coherent with Mach's principle; the emitter creates dissymmetry and the differential between the advanced and retarded field
components create energy, gravitation, and the acceleration H c.
In classical electrodynamics, the radiating source is accompanied by a radiation field--the classical retarded field
of the source (CRS), which reaches the particles in the absorber, and accelerates them in turn.
As Leeds explains, Feynman and Wheeler propose that the field associated with i is 1/2(CRS + CAS), where CRS (in Leeds' terminology) is the classical retarded field - the outgoing wave leaving i at t which is what we normally 'see' - and CAS is the classical advanced field - i.
In the space-time region between i and the absorbing shell, after the time t, it now becomes simply CRS: in other words, it is identical to the classical retarded field from i at t.
ret [mu][alpha]] is the retarded field
tensor due to the i- th charged particle in an absorber containing n particles, and where the [v.
1/2(CRS + CAS)); each particle in the absorber produces an advanced field of 1/2 the magnitude of the retarded field it would produce according to the classical prescription.
2 Notice that Wheeler and Feynman neglect the retarded field set up by the absorber in response to the wave CRS transmitted from source to absorber.
It provides a survey of vector field theory and covers everything from retarded fields
to antenna theory and Faraday rotation, pairing discussions and science with plenty of examples and calculations suitable for college-level students.