In this case it's a description of the 6-dimensional coordinates used in Lagrangian mechanics, which dates to the late 1700s. https://en.wikipedia.org/wiki/Lag

In this case it's a description of the 6-dimensional coordinates used in Lagrangian mechanics, which dates to the late 1700s. https://en.wikipedia.org/wiki/Lagrangian_mechanics https://en.wikipedia.org/wiki/Lagrangian_mechanics https://en.wikipedia.org/wiki/Position_and_momentum_space https://en.wikipedia.org/wiki/Position_and_momentum_space The symplectic geometry from the article is an abstract version of ideas from Hamiltonian mechanics, which is from the early 1800s. https://en.wikipedia.org/wiki/Hamiltonian_mechanics https://en.wikipedia.org/wiki/Hamiltonian_mechanics