Cancellations Beyond Finiteness in N=8 Supergravity at Three Loops
Abstract
We construct the threeloop fourpoint amplitude of N=8 supergravity using the unitarity method. The amplitude is ultraviolet finite in four dimensions. Novel cancellations, not predicted by traditional superspace powercounting arguments, render its degree of divergence in D dimensions no worse than that of N=4 superYangMills theorya finite theory in four dimensions. Similar cancellations can be identified at all loop orders in certain unitarity cuts, suggesting that N=8 supergravity may be a perturbatively finite theory of quantum gravity.
 Authors:
 Department of Physics and Astronomy, UCLA, Los Angeles, California 900951547 (United States)
 Stanford Linear Accelerator Center, Stanford University, Stanford, California 94309 (United States)
 Service de Physique Theorique, CEASaclay, F91191 GifsurYvette cedex (France)
 (Switzerland)
 Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)
 Publication Date:
 OSTI Identifier:
 20951248
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 16; Other Information: DOI: 10.1103/PhysRevLett.98.161303; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; AMPLITUDES; QUANTUM GRAVITY; SUPERGRAVITY; ULTRAVIOLET RADIATION; UNITARITY; YANGMILLS THEORY
Citation Formats
Bern, Z., Carrasco, J. J., Johansson, H., Dixon, L. J., Kosower, D. A., Institut fuer Theoretische Physik, Universitaet Zuerich, CH8057 Zurich, and Roiban, R. Cancellations Beyond Finiteness in N=8 Supergravity at Three Loops. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVLETT.98.161303.
Bern, Z., Carrasco, J. J., Johansson, H., Dixon, L. J., Kosower, D. A., Institut fuer Theoretische Physik, Universitaet Zuerich, CH8057 Zurich, & Roiban, R. Cancellations Beyond Finiteness in N=8 Supergravity at Three Loops. United States. doi:10.1103/PHYSREVLETT.98.161303.
Bern, Z., Carrasco, J. J., Johansson, H., Dixon, L. J., Kosower, D. A., Institut fuer Theoretische Physik, Universitaet Zuerich, CH8057 Zurich, and Roiban, R. Fri .
"Cancellations Beyond Finiteness in N=8 Supergravity at Three Loops". United States.
doi:10.1103/PHYSREVLETT.98.161303.
@article{osti_20951248,
title = {Cancellations Beyond Finiteness in N=8 Supergravity at Three Loops},
author = {Bern, Z. and Carrasco, J. J. and Johansson, H. and Dixon, L. J. and Kosower, D. A. and Institut fuer Theoretische Physik, Universitaet Zuerich, CH8057 Zurich and Roiban, R.},
abstractNote = {We construct the threeloop fourpoint amplitude of N=8 supergravity using the unitarity method. The amplitude is ultraviolet finite in four dimensions. Novel cancellations, not predicted by traditional superspace powercounting arguments, render its degree of divergence in D dimensions no worse than that of N=4 superYangMills theorya finite theory in four dimensions. Similar cancellations can be identified at all loop orders in certain unitarity cuts, suggesting that N=8 supergravity may be a perturbatively finite theory of quantum gravity.},
doi = {10.1103/PHYSREVLETT.98.161303},
journal = {Physical Review Letters},
number = 16,
volume = 98,
place = {United States},
year = {Fri Apr 20 00:00:00 EDT 2007},
month = {Fri Apr 20 00:00:00 EDT 2007}
}
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ThreeLoop Superfiniteness of N=8 Supergravity
We construct the threeloop fourpoint amplitude of N = 8 supergravity using the unitarity method. The amplitude is ultraviolet finite in four dimensions. Novel cancellations, not predicted by traditional superspace powercounting arguments, render its degree of divergence in D dimensions to be no worse than that of N = 4 superYangMills theorya finite theory in four dimensions. Similar cancellations can be identified at all loop orders in certain unitarity cuts, suggesting that N = 8 supergravity may be a perturbatively finite theory of quantum gravity. 
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