"In 1934, L.E.Kinsler at the California Institute of technology was studying the Zeeman effect as a means for evaluating the charge-to-mass ratio of the electron, e/m. The deduction of e/m from the measured wavelength differences involves, in addition to a high-precision measurement of the magnetic field, a knowledge of the way in which the individual electron spins and orbital angular momenta are coupled. However, there are certain quantities or combinations of quantities that are independent of the nature of the coupling. One such combination is provided for by a relation called the g-sum rule, which states that the sum of the values of for all the states with a given value of J formed from a given combination of single-electron states is independent of the coupling. Kinsler undertook to test this rule, using two states in neon that involved five electrons in 2p states and one in a 3s state.[...]
Kinsler's measurements gave , .
The discrepancies from the values are substantial but are presumably to be ascribed to the imperfectness of the L-S description. The g-sum rule is another matter: .
Kinsler simply added the errors on the individual values and quoted a resultant error of 0.0016, so that the discrepancy was regarded as insignificant. [...] If the individual errors were independent, a better overall uncertainty would have been the square root of the sum of the squares, or 0.0011, making the discrepancy large enough to be taken seriously. [...]
Even if Kinsler had believed his result, however, the tone of his paper suggests that he would have ascribed it to the failure of the g-sum rule rather than to an anomalous value of . On such minor things does the course of events depend!"
George L. Trigg, Landmark Experiments in Twentieth Century Physics, Crane (NY) 1975.
- PHYSICAL SCIENCES
- EARTH SCIENCES
- LIFE SCIENCES
- SOCIAL SCIENCES
Subscribe to the newsletter
Stay in touch with the scientific world!
Know Science And Want To Write?
- Is That A Real Patient Or A Junkie? Now There's An App For That
- You Are Ready To Eat Insects If You Have These Characteristics
- How The Higgs Became The Target Of Run 2 At The Tevatron
- How Neuroscience Is Being Used To Spread Quackery In Business And Education
- Global 'Roadmap' Shows Where To Put Roads Without Costing The Earth
- MOOCs: Learning About Online Learning, One Click At A Time
- Will We Meet ET Microbes On Mars? Why We Should Care Deeply About Them - Like Tigers
- "You guessed alright, that is a page from the book...Cheers,T...."
- "Dear Anon,in 1994 neutrinos were not the main focus of the lab...Cheers,T...."
- "I did not ignore your 4x4 matrices comment, as I explained in the very message you were replying..."
- "I do not know which P5 meeting you attended, but in the mind of the current fnal director, fnal..."
- "Cool. I really look forward for your book! I still remember the excitement of my times at fnal... K...."
- Geochronology and global context of the Charnian Supergroup
- Confirmation of a low pre-extensional geothermal gradient in the Grayback normal
- Scientists get set for simulated nuclear inspection
- Invisible blood in urine may indicate bladder cancer
- Sugar substance 'kills' good HDL cholesterol, new research finds