Double copy theory

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Double copy theory is a theory in theoretical physics, specifically in quantum gravity, that hypothesizes a perturbative duality between gauge theory and gravity. The theory says that scattering amplitudes in non-Abelian gauge theories can be factorized such that replacement of the color factor by additional kinematic dependence factor, in a well-defined way, automatically leads to gravity scattering amplitudes. It was first written down by Zvi Bern, John Joseph Carrasco and Henrik Johansson in 2010 [1] and was sometimes known as the BCJ duality after its creators [2] or as "gravity = gauge × gauge". [3]

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The theory can be used to make calculations of gravity scattering amplitudes simpler by instead calculating the Yang–Mills amplitude and following the double copy prescription. [4] This technique has been used, for example, to calculate the shape of gravitational waves emitted by two merging black hole. [5] [6] This was proven to work at tree level and at higher orders, [1] including at fourth post-Minkowskian order. [7] The theory has been applied to black holes. [8]

See also

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References

  1. 1 2 Bern, Zvi; Carrasco, John Joseph M; Johansson, Henrik (2010). "Perturbative Quantum Gravity as a Double Copy of Gauge Theory". Physical Review Letters. 105 (6): 061602. arXiv: 1004.0476 . Bibcode:2010PhRvL.105f1602B. doi:10.1103/PhysRevLett.105.061602. PMID   20867971. S2CID   35590493.
  2. Oxburgh, S. and White, C.D. (22 February 2013). "BCJ duality and the double copy in the soft limit". J. High Energy Phys. 2013 (127): 127. arXiv: 1210.1110 . Bibcode:2013JHEP...02..127O. doi:10.1007/JHEP02(2013)127. S2CID   119175289.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  3. Borsten, L. (11 March 2020). "Gravity as the square of gauge theory: a review". La Rivista del Nuovo Cimento. 43 (3): 97–186. Bibcode:2020NCimR..43...97B. doi:10.1007/s40766-020-00003-6. S2CID   216347827.
  4. White, C. D. (12 January 2018). "The double copy: gravity from gluons". Contemporary Physics. 59 (2): 109–125. arXiv: 1708.07056 . Bibcode:2018ConPh..59..109W. doi:10.1080/00107514.2017.1415725. S2CID   118863994.
  5. Goldberger, Walter D.; Ridgway, Alexander K. (2017-06-30). "Radiation and the classical double copy for color charges". Physical Review D. 95 (12): 125010. arXiv: 1611.03493 . Bibcode:2017PhRvD..95l5010G. doi:10.1103/PhysRevD.95.125010. S2CID   22057355.
  6. Wood, Charlie (2022-03-29). "Massive Black Holes Shown to Act Like Quantum Particles". Quanta Magazine. Retrieved 2022-04-06.
  7. Bern, Zvi; Parra-Martinez, Julio; Roiban, Radu; Ruf, Michael S.; Shen, Chia-Hsien; Solon, Mikhail P.; Zeng, Mao (2021-04-26). "Scattering Amplitudes and Conservative Binary Dynamics at ${\cal O}(G^4)$". Physical Review Letters. 126 (17): 171601. arXiv: 2101.07254 . doi: 10.1103/PhysRevLett.126.171601 . ISSN   0031-9007. PMID   33988437.
  8. Monteiro, Ricardo; O'Connell, Donal; White, Chris D (2014). "Black holes and the double copy". Journal of High Energy Physics. 2014 (12): 56. arXiv: 1410.0239 . Bibcode:2014JHEP...12..056M. doi:10.1007/JHEP12(2014)056. S2CID   52994864.