Mirage stated: source post
Cricket got that shit covered +10
Empty is a temporary impasse in decision making, when being nothing is preferable to x situation or when you're deeply affected by a failure/mistake/loss.
Hunger is everyday, every minutes of non-emptyness. it's the force that drive you forward, that pushes you to seek out more and more to feed your insatiable ego.
I think emptyness is just how we, who haven't been gifted with deep complex feelings, experience depression. Just as fleeting as any other emotions we feel.
Mir's description is a good clarification of my wordiness. Though I would add in that empty can be felt after a significant accomplishment and no rush is provided.