Many energy conditions have been shown to be violated in the past in semiclassical gravity, for instance when considering Klein-Gordon quantum scalar fields. Victims include the WEC (Weak Energy Condition), NEC (Null Energy Condition), SEC (Strong Energy Condition), DEC (Dominant Energy Condition).
About 15 years ago, the AANEC (Achronal averaged null energy condition) was introduced as a weaker energy condition, which is expected to be respected in all well behaved solutions, while being violated in exotic solutions such as wormholes and warp drives.
Are there any known violations to the AANEC?
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