The high-energy collision of black holes in higher dimensions

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Cook, William 
Wang, Diandian 

We compute the gravitational wave energy Erad radiated in head-on collisions of equal-mass, nonspinning black holes in up to D=8 dimensional asymptotically flat spacetimes for boost velocities v up to about 90% of the speed of light. We identify two main regimes: Weak radiation at velocities up to about 40% of the speed of light, and exponential growth of Erad with v at larger velocities. Extrapolation to the speed of light predicts a limit of 12.9% (10.1, 7.7, 5.5, 4.5)%. of the total mass that is lost in gravitational waves in D=4 (5,6,7,8) spacetime dimensions. In agreement with perturbative calculations, we observe that the radiation is minimal for small but finite velocities, rather than for collisions starting from rest. Our computations support the identification of regimes with super Planckian curvature outside the black-hole horizons reported in Okawa et al [1].

gr-qc, gr-qc, hep-th
Journal Title
Physical Review D: Particles, Fields, Gravitation and Cosmology
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American Physical Society
All rights reserved
European Research Council (646597)
European Commission Horizon 2020 (H2020) Marie Sk?odowska-Curie actions (690904)
Science and Technology Facilities Council (ST/P000673/1)
Science and Technology Facilities Council (ST/R002452/1)
Science and Technology Facilities Council (ST/R00689X/1)
Science and Technology Facilities Council (ST/M007065/1)
STFC (ST/M007073/1)
STFC (ST/T001550/1)
This work was supported by the European Unions H2020 ERC Consolidator Grant Matter and strong- eld gravity: new frontiers in Einsteins theory grant agreement no. MaGRaTh{646597, funding from the European Unions Horizon 2020 research and innovation programme under the Marie Sk lodowska-Curie grant agreement No 690904, the COST Action Grant No. CA16104, from STFC Consolidator Grant No. ST/P000673/1, the SDSC Comet and TACC Stampede2 clusters through NSF-XSEDE Award No. PHY-090003, and Cambridges CSD3 system system through STFC capital grants ST/P002307/1 and ST/R002452/1 and STFC operations grant ST/R00689X/1. D.W. acknowledges support by a Trinity College Summer Research Fellowship. W.C. is supported by The Simons Foundation award no. 548512, and the Princeton Gravity Initiative.