#### learningphysics

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I have some questions regarding the first two sections Einstein's paper. I'd really appreciate some guidance.

The paper can be found here:

http://lorentz.phl.jhu.edu/AnnusMirabilis/AeReserveArticles/eins_lq.pdf

In section 1 of the paper, he considers a volume of gas surrounded by reflective walls. He goes on to derive what seems to me to be the Rayleigh-Jeans law using "Maxwell theory" and "kinetic gas theory".

[tex]\rho_\nu = \frac{R}{N} \frac{8\pi{\nu}^2}{L^3}T[/tex]

R/N = k (boltzmann constant) and L = c

Then in section 2... he writes:

"We shall show in the follow that determination of elementary quanta given by Mr. Plank is, to a certain extent, independent of the theory of "black-body radiation" constructed by him.

He writes Planck's formula:

[tex]\rho_\nu = \frac{\alpha {\nu}^3}{e^{\beta\nu/T}-1}[/tex]

and then shows that at large [tex]T/\nu[/tex] this leads to the rayleigh jeans law.

It seems like what Einstein's showing is... first...

"maxwell theory" and "kinetic gas theory" => Rayleigh Jeans Law

then

"planck's formula" => Rayleigh Jeans Law

Is this to demonstrate that Planck's formula is not just applicable to blackbodies? But I thought both of these were already known. It seems to me that there is something significant Einstein's getting at here, but I'm missing it.

I'd appreciate any help.

The paper can be found here:

http://lorentz.phl.jhu.edu/AnnusMirabilis/AeReserveArticles/eins_lq.pdf

In section 1 of the paper, he considers a volume of gas surrounded by reflective walls. He goes on to derive what seems to me to be the Rayleigh-Jeans law using "Maxwell theory" and "kinetic gas theory".

[tex]\rho_\nu = \frac{R}{N} \frac{8\pi{\nu}^2}{L^3}T[/tex]

R/N = k (boltzmann constant) and L = c

Then in section 2... he writes:

"We shall show in the follow that determination of elementary quanta given by Mr. Plank is, to a certain extent, independent of the theory of "black-body radiation" constructed by him.

He writes Planck's formula:

[tex]\rho_\nu = \frac{\alpha {\nu}^3}{e^{\beta\nu/T}-1}[/tex]

and then shows that at large [tex]T/\nu[/tex] this leads to the rayleigh jeans law.

It seems like what Einstein's showing is... first...

"maxwell theory" and "kinetic gas theory" => Rayleigh Jeans Law

then

"planck's formula" => Rayleigh Jeans Law

Is this to demonstrate that Planck's formula is not just applicable to blackbodies? But I thought both of these were already known. It seems to me that there is something significant Einstein's getting at here, but I'm missing it.

I'd appreciate any help.

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