![](https://www.geni.com/images/external/x_com_black_16.png?1718400071)
![](https://www.geni.com/images/facebook_white_small_short.gif?1718400071)
timeline (wiki) 1859 – Gustav Kirchhoff introduces the concept of a blackbody and proves that its emission spectrum depends only on its temperature. 1860–1900 – Ludwig Eduard Boltzmann , James Clerk Maxwell and others develop the theory of statistical mechanics. Boltzmann argues that entropy is a measure of disorder. 1877 – Boltzmann suggests that the energy levels of a physical sys...