Can someone explain what's groundbreaking about this? Maybe it's not done so very rigorously, but pretty much every plasma physics textbook will contain a deriv

Can someone explain what's groundbreaking about this? Maybe it's not done so very rigorously, but pretty much every plasma physics textbook will contain a derivation of Boltzmann equation, including some form of collisional operator, starting from Liouville's theorem[1] and then derive a system of fluid equations [2] by computing the moments of Boltzmann equation. [1]: https://en.wikipedia.org/wiki/Liouville%27s_theorem_(Hamiltonian) https://en.wikipedia.org/wiki/Liouville%27s_theorem_(Hamilto... [2]: https://en.wikipedia.org/wiki/BBGKY_hierarchy https://en.wikipedia.org/wiki/BBGKY_hierarchy