Unification: SDEs, Probability Flow ODEs, and Fokker-Planck Dynamics
An interactive live film: microscopic random SDE paths and smooth deterministic ODE streamlines are united by the macroscopic Fokker-Planck probability current, yielding identical density marginals at every moment.
Narration
We have seen three different languages for diffusion models: stochastic differential equations, probability flow ordinary differential equations, and the Fokker-Planck equation.
At the macroscopic level, the Fokker-Planck equation describes the conservation of probability mass. The rate of change of density equals minus the divergence of current.
The rest of the narration is in the book's Companion.
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