KLT relations



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The KLT relations express certain scattering amplitudes in gravity equivalently in terms of scattering amplitudes in Yang-Mills theory.

These relations are manifest in string theory-UV-completions of gravity+Yang-Mills theory, where they were originally found and from which the QFT relations have been deduced: in string theory the graviton is an excitation of the closed string and the gluon of the open string. But disk-shaped string diagram can be read in two-ways: either as a closed-string vacuum diagram or as an open-string tree-level scattering diagram. This open/closed string duality of string scattering amplitudes yields the KLT relations.


  • Zvi Bern, The KLT relations in field theory, Living Reviews in Relativity

  • Zvi Bern, Perturbative Quantum Gravity and its Relation to Gauge Theory, LivingRev.Rel.5:5,2002 (arXiv:gr-qc/0206071)

  • N. E. J. Bjerrum-Bohr, K. Risager, String theory and the KLT-relations between gravity and gauge theory including external matter (arXiv:hep-th/0407085)

  • Zvi Bern, The S-matrix reloaded: Twistors, Unitarity, Gauge theories and Gravity, 2005 (pdf)

  • Zvi Bern, John Joseph Carrasco, Lance Dixon, Henrik Johansson, Radu Roiban, Amplitudes and Ultraviolet Behavior of N=8 Supergravity (arXiv:1103.1848)

  • Bo Feng, Song He, Rijun Huang, Yin Jia, Note on New KLT relations (arXiv:1008.1626)

  • Zvi Bern, John Joseph M. Carrasco, Henrik Johansson, Perturbative Quantum Gravity as a Double Copy of Gauge Theory, Phys. Rev. Lett. 105, 061602 – Published 3 August 2010 (arXiv:1004.0476)

  • Dhritiman Nandan, Jan Plefka, Oliver Schlotterer, Congkao Wen, Einstein-Yang-Mills from pure Yang-Mills amplitudes (arXiv:1607.05701)

Revised on November 20, 2017 14:14:14 by Urs Schreiber (