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Elementary charge
and The Golden Section
The electron is a fundamental subatomic particle that carries a negative electric charge. Together with atomic nuclei (protons and neutrons), electrons make up atoms.
The discovery that the electron was a subatomic particle was made in 1897 by J.J. Thomson at the Cavendish Laboratory at Cambridge University, while he was studying cathode ray tubes.
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On April 30, 1897, Thomson announced that cathode rays were negatively charged particles which he called 'corpuscles.' He also announced that they had a mass about 1000 times smaller than a hydrogen atom, and he claimed that these corpuscles were the things from which atoms were built up. Thomson's corpuscle hypothesis was not generally accepted, even by British scientists, until he spoke of it again in 1899. By this time, George Francis FitzGerald (1851-1901), had suggested that Thomson's 'corpuscles' making up the cathode ray were actually free electrons. In fact, this suggestion was published as a commentary to the publication of Thomson's April 30, 1897 lecture in which he first announced his results. Thomson himself continued to use the term corpuscle until 1913.
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Other people had measured the e/m ratio or suggested that the cathode rays were composed of particles, but Thomson was the first to say that the cathode ray was a building block of the atom. It was a risky thing, but he was proved right and for his courage he is remembered as the discoverer of the electron.
The connection between electron charge on one side and , The Golden section on the other, is highly amusing:
where phi is the value of the golden section and PI is Archimedes` constant:
and where are:
Using the best experimental values for r,R,h_bar and (the value of c is fixed by definition) gives:
Elementary charge: The CODATA 2006 recommended value :
See: Planck`s constant and number PI
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Planck, M. "Zur Theorie des Gesetzes der Energieverteilung im Normalspektrum." Verhandl. Deutsch. phys. Ges. 2, 237, 1900.
P. A. M. Dirac, Nature 139, 323 (1937)
Dirac, P.A.M. Principles of Quantum Mechanics, 4th ed. Oxford, England: Oxford University Press, 1982.
B.W.Petley: The Fundemental Physical Constants and the Frontier of Measurement" Adam Hilger Ltd. Bristol UK, 1985.
Hans A.Bethe: "Intermediate Quantum Mechanics",W.A.Benjamin Inc,New York - Amsterdam (1964).
Srpska Akademija nauka i umetnosti: "Elektron-sto godina od otkrica",
Zavod za udzbenike i nastavna sredstva, Beograd (1997)
Todorovic,Milan: "Atomska fizika".Elektrotehnicki fakultet, Beograd (1973).
Ivanovic,Dragisa: "Kvantna mehanika".Naucna knjiga, Beograd (1972).
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