On the positivity of light-ray operators

Ben Freivogel, Hidde Stoffels

We consider light-ray operators ${\mathcal{L}}_{2n}=\int \mathrm{d}{x}^{+}(x^{+}{)}^{2n}{T}_{++}$, where $x^{+}$ is a null coordinate and $n$ a positive integer, in QFT in Minkowski spacetime…