We are trying to minimize the depicted function f(x,y) given some initial positions and the local gradient ∇f(x,y). The green circle represents the initial position, blue circles depict ADAM updates, red circles SGD updates. The vector lines coming out of the circles are the gradients. Playing with β1 and β2 in ADAM will reveal where the physics-borrowed "momentum" nomenclature comes from.
georggrab.net