# Null energy conditions in quantum field theory

@article{Fewster2003NullEC, title={Null energy conditions in quantum field theory}, author={Christopher J. Fewster and Thomas A. Roman}, journal={Physical Review D}, year={2003}, volume={67}, pages={044003} }

For the quantized, massless, minimally coupled real scalar field in four-dimensional Minkowski space, we show (by an explicit construction) that weighted averages of the null-contracted stress-energy tensor along null geodesics are unbounded from below on the class of Hadamard states. Thus there are no quantum inequalities along null geodesics in four-dimensional Minkowski spacetime. This is in contrast with the case for two-dimensional flat spacetime, where such inequalities do exist. We…

## 64 Citations

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