Beginnings The development of the helicon or toroidal ring began with
André-Marie Ampère, who in 1823 proposed tiny magnetic "loops of charge" to explain the attractive force between current elements. In that same era
Carl Friedrich Gauss and
Michael Faraday also uncovered foundational laws of
classical electrodynamics, later collected by
James Maxwell as
Maxwell's equations. When Maxwell expressed the laws of
Gauss,
Faraday, and
Ampère in
differential form, he assumed
point particles, an assumption that remains foundational to
relativity theory and
quantum mechanics today. In 1867
Lord Kelvin suggested that the
vortex rings of a
perfect fluid discovered by
Hermann von Helmholtz represented "the only true
atoms". Then shortly before 1900, as scientists still debated over the very existence of atoms,
J. J. Thomson and
Ernest Rutherford sparked a revolution with experiments confirming the existence and properties of electrons, protons, and
nuclei.
Max Planck added to the fire when he solved the
blackbody radiation problem by assuming not only
discrete particles, but discrete
frequencies of radiation emanating from these "particles" or "
resonators". Planck's famous paper, which incidentally calculated both the
Planck constant h and the
Boltzmann constant kB, suggested that something in the "resonators" themselves provided these discrete frequencies. Numerous
theories about the structure of the atom developed in the wake of all the new information, of which the 1913 model of
Niels Bohr came to predominate. The
Bohr model proposed electrons in circular orbit around the
nucleus with
quantized values of
angular momentum. Instead of
radiating energy continuously, as
classical electrodynamics demanded from an accelerating charge, Bohr's electron radiated discretely when it "
leaped" from one
state of angular momentum to another.
Parson magneton In 1915,
Alfred Lauck Parson proposed his "
magneton" as an improvement over the
Bohr model, depicting finite-sized particles with the ability to maintain
stability and
emit and
absorb radiation from
electromagnetic waves. At about the same time
Leigh Page developed a
classical theory of
blackbody radiation assuming rotating "
oscillators", able to store energy without radiating.
Gilbert N. Lewis was inspired in part by Parson's model in developing his theory of
chemical bonding. Then
David L. Webster wrote three papers connecting Parson's magneton with Page's oscillator and explaining
mass and
alpha scattering in terms of the magneton. In 1917
Lars O. Grondahl confirmed the model with his experiments on free electrons in
iron wires. Parson's theory next attracted the attention of
Arthur Compton, who wrote a series of papers on the properties of the electron, and
H. Stanley Allen, whose papers also argued for a "ring electron". == Current status ==