Phantom energy is an exotic form of dark energy that possesses negative energy, which means that its pressure is negative and its energy density is greater than its critical density. This would imply that the energy density of phantom energy would increase as the universe expands, eventually leading to a Big Rip.
This is exotic energy in which a vacuum is unstable with negative mass particles bursting into existence via averaged null energy conditions (ANEC).
Uses:
- Keeps traversable wormholes open, which use a relatively small amount of ANEC-violating energy, but need to be located in a region of flat space.
- Used for communication wormholes, which use a much larger amount of ANEC-violating energy.
- Reactionless and perpetual motion drives
- Stabilizing the void or warp bubbles used in warp drives