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pflats
·2 ปีที่แล้ว·discuss
I was curious, so I grabbed three undergraduate-level physics texts I had nearby.

One explicitly recites the Ultraviolet Catastrophe prompted Planck story, complete with Rayleigh's incomplete formula.

One essentially matches the story in section 2, using the lesser version of Rayleigh's formula, but (just like the story) does not explicitly tie Planck's work to it. (That textbook notes "an act of desperation" is a quote from one of Planck's letters.)

The third one is interesting! It says that "late nineteenth century physicists tried to understand the shape of the blackbody spectrum [...] using their knowledge of thermodynamics and electromagnetic waves. Their efforts ended in failure." This third text never mentions Rayleigh by name and doesn't specifically show "Rayleigh's Lesser Formula", but it does graph that formula vs. the observed blackbody radiation (interestingly, as a function of frequency instead of wavelength).

The text then eventually says that in 1900, Planck used a photon argument "to make a theoretical prediction that is in excellent agreement with the experimental spectrum". It does not explicitly state cause and effect, but it's kinda implied from the structure of the writing.

Reading into the third text a smidge, it feels like the result of wanting to use the Rayleigh/Catastrophe story and yet knowing it wasn't quite true.
pflats
·2 ปีที่แล้ว·discuss
Suppose an author uploads their book to ExamplePrint Inc, a one stop shop that prints made-to-order books for customers.

The reader goes to ExamplePrint and buys the book.

ExamplePrint prints a softcover copy of the book on the spot and ships it out to the reader.

The user pays ExamplePrint, who pays the author some fraction of the user's money.

The reader is a customer of ExamplePrint and reading the author's book.

This is the analogy Apple would like to use for their app store. Apple's print time is almost instantaneous and the marginal costs are closer to zero.
pflats
·10 ปีที่แล้ว·discuss
Every time I read another article on this, it makes me more skeptical about Zuckerberg's for-profit "charity".