Symmetry refers to a sense of harmonious and beautiful proportion and balance. (Wikipedia)
is sound you FEEL as much as you hear. Ideally, the user / listener understands more about the interaction model by hearing UX audio.
is the new evolutionary step in interactive audio. Instead of action coming from the screen, you are inside the screen. Audio must represent the same depth of immersion.
is even more abstract than VR. There is no screen. Augmented / holographic objects must seem like they exist naturally in your environment while amplifying your reality.