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I'm rereading Brian Greene's "The Fabric of the Universe". I like it because he explains the physics of space, energy/matter and time pretty well without getting into too much math (which, in quantum mechanics and relativity theories, is way, way over my head). One of the things that I'm really curious about is how the planck constants that he mentions, e.g., planck length and planck time, are "derived" (if that's the right term). I've tried to do internet searches, but usually all I get are sites that explain how planck constants are used - which I kind of understand - not how they are derived. How did Planck come up with the constant(s)? Is it some kind of ratio? If so, a ratio of what to what?
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eyes... rolling... back... into... head
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mikebw wrote:
[quote Max Planck]it would after all be only an interpolation formula found by happy guesswork
http://www.spaceandmotion.com/Physics-Max-Planck.htm
Thanks for the link, mikebw, but unless I missed it, it didn't explain the actual method he used to come up with the constant(s) we call planck constant(s). Did he just do trial and error zeroing in on a value that worked out consistent with measurements or is the value of the constant(s) actually derived from other factors?
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Overheard in Planck's lab........
Lets try..........
THIS!!!!!
6.626068 × 10-34 m2 kg / s
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My grandmother used
to have a physic when Planckton's got her pooper stuck....:devil:
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Duh, I think I found the answer to my question - in Wikipedia. Don't know why I didn't look there earlier:
http://en.wikipedia.org/wiki/Planck_constant#Origins
Planck hypothesized that the equations of motion for light are a set of harmonic oscillators, one for each possible frequency. He examined how the entropy of the oscillators varied with the temperature of the body, trying to match Wien's law, and was able to derive an approximate mathematical function for black-body spectrum.[4]
However, Planck soon realized that his solution was not unique. There were several different solutions, each of which gave a different value for the entropy of the oscillators[4]. To save his theory, Planck had to resort to using the then controversial theory of statistical mechanics,[4] which he described as "an act of despair … I was ready to sacrifice any of my previous convictions about physics."[5] One of his new boundary conditions was to interpret UN not as a continuous, infinitely divisible quantity, but as a discrete quantity composed of an integral number of finite equal parts.
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