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arXiv · 1810.05706

Light-ray Operators and the BMS Algebra

Clay Cordova·Shu-Heng Shao
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Abstract

We study light-ray operators constructed from the energy-momentum tensor in $d$-dimensional Lorentzian conformal field theory. These include in particular the average null energy operator. The commutators of parallel light-ray operators on a codimension one light-sheet form an infinite-dimensional algebra. We determine this light-ray algebra and find that the $d$-dimensional (generalized) BMS algebra, including both the supertranslation and the superrotation, is a subalgebra. We verify this algebra in correlation functions of free scalar field theory. We also determine the infinite-dimensional algebra of light-ray operators built from non-abelian spin-one conserved currents.

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Clay Cordova, Shu-Heng Shao. 2018-10-12. Light-ray Operators and the BMS Algebra. https://doi.org/10.1103/physrevd.98.125015

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