I'm not sure what this has to do with "movement" really, but white dwarfs stars only don't collapse if they are held up by the appropriate electron degeneracy pressure
. The electrondegerenate matter is held apart due to the Pauli Exclusion principle, which says that two fermions can't occupy the same quantum state, thus limiting the distance between matter in the star. You should read about the Chandrasekhar Limit
for full details though, because White Dwarfs can collapse/supernovae.