http://www.hyiq.org/Library/E.T.Whittaker-1904.pdf [Broken] "On an Expression of the Electromagnetic Field due to Electrons by Means of Two Scalar Potential Functions" by E. T. Whittaker published in Proceedings of the London Mathematical Society, Vol. 1, 1904) In the paper Whittaker 1904 seemed to show that all EM fields and waves can be decomposed into two scalar potential functions. It follows that, by assembling two such scalar potential functions in beams, one can produce a "scalar potential interferometer" where the potential beams intersect at a distance. In that interference zone, ordinary transverse EM fields and energy appear. You may state that it was written prior to special relativity. But note that maxwell equations are naturally lorentz invariant.. so Whittaker paper would still be in full force. Can anyone point out any flaw in the paper that would make the above not possible? Note Whittaker is one major player and part of early 20th century physics akin to Poincare or Lorentz. Whittaker was, in 1954, selected by the Fellows of the Royal Society to receive the Copley Medal, the highest award granted by the scientific Royal Society of London, "for his distinguished contributions to both pure and applied mathematics and to theoretical physics". Back in 1931 Whittaker had received the Royal Society's Sylvester Medal "for his original contributions to both pure and applied mathematics". What made him write the paper and what is it really all about?