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arXiv · 2203.13019

The SAGEX Review on Scattering Amplitudes, Chapter 8: Half BPS correlators

Paul Heslop
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Abstract

Half BPS correlators in N=4 super Yang-Mills theory are key quantities both in the AdS/CFT correspondence as well as in scattering amplitudes research. They are dual at strong coupling to quantum gravity amplitudes. At weak coupling on the other hand they contain all N=4 SYM amplitudes. They have been found to possess a number of hidden symmetries, for example non-trivial permutation symmetry of perturbative four-point integrands and a higher dimensional conformal symmetry. Their study has enjoyed continuous progress since the discovery of AdS/CFT and they are now some of the best understood quantities of any four-dimensional quantum field theory. In this review we outline the current knowledge of half BPS correlators, emphasising these two co-existing relations to scattering amplitudes at strong and weak coupling.

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Paul Heslop. 2023-01-17. The SAGEX Review on Scattering Amplitudes, Chapter 8: Half BPS correlators. https://doi.org/10.1088/1751-8121%2Fac8c71

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