Brad Klee <bradklee@gmail.com> wrote:
I alluded to metrology of SI by mentioning Caesium hyperfine. This is a justification for projective formalism: there is an agreed upon standard for how to set absolute value 1 in each dimension.
Right. Time is really several similar but subtly different concepts. The cesium clock pins down which one we're using. Also, the time of day is given, not just by any cesium clock, but only by one on the geoid (roughly speaking, at mean sea level). In principle, time as measured by each of the four forces could be different, in which case the cesium clock implies we're using time based on the electromagnetic force. Similarly, the original definition of the gram implied that "pure water" is well defined. Actually, it can have a varying isotopic composition, hence a range of densities.
As for time dependence of fine structure, Ralston discusses this in his article on Planck?s constant:
https://arxiv.org/abs/1203.5557 ( worth the time to read )
He was against the recent decision to fix Planck?s constant.
I could make no sense of that paper. I can't figure out what he means by abolishing the Planck constant. Setting it to 1? The Planck system of units does exactly that, as it sets it, c, G, and k-sub-B to 1. But its usefulness is limited by the low precision to which G is known, and by the inconvenient sizes of most units. Obviously the Planck constant can't be set to 1 within SI, as that would radically change the sizes of lots of units. Perhaps he means it should be regarded as dimensionless? That would make action and angular momentum dimensionless, meaning that energy and frequency would be considered the same thing. And so would distance and momentum. That doesn't sound useful to me. Anyhow, the Planck constant would still exist, though it would become a mere conversion factor, the number of hertz in a joule, like the number of feet in a mile. If he's arguing that its numerical value is arbitrary, a mere artifact of our system of units, I don't know of anyone who disagrees. He argues that if it was abolished, other constants could be determined better. But that's exactly what the 2019 SI changes did, and a large part of why they were adopted. And you say he was against those changes. Not having gone to college, I'm reluctant to argue with people with doctorates, especially doctorates in hard sciences. Does the fact that he misspells Rydberg and calls Kelvins "degrees Kelvin" count against him, or does it just mean I have the soul of a proofreader? So, is he confused, or am I? If the latter, can someone explain his central thesis to me? Thanks.