Page:Zur Theorie der Strahlung in bewegten Körpern. Berichtigung.djvu/4

corrected value $\varkappa '$. However, now the contraction hypothesis of Lorentz and Fitzgerald doesn't suffice anymore as the solution of the resulting contradiction with the second thermodynamic theorem, so one would still have to add the hypothesis, that the true emission capability of a black body explicitly depends on the motion, namely by the factor $1-{\tfrac {2}{3}}\beta ^{2}$, a hypothesis whose possibility I already considered in the mentioned paper.

If it is generally assumed, that the dimensions of matter (in the direction of motion) have to be multiplied by $\lambda$, and the true emission capability with $\sigma$, then it must be

$\lambda ^{-3/4}\cdot \sigma ^{-1}=1+{\frac {4}{3}}\beta ^{2}$

Vienna, January 1905.

(Received January 26, 1905).