An R^4 non-renormalisation theorem in N=4 supergravity
High Energy Physics - Theory
2015-06-04 v4
Abstract
We consider the four-graviton amplitudes in CHL constructions providing four-dimensional N=4 models with various numbers of vector multiplets. We show that in these models the two-loop amplitude has a prefactor of d^2R^4. This implies a non-renormalisation theorem for the R^4 term, which forbids the appearance of a three-loop ultraviolet divergence in four dimensions in the four-graviton amplitude. We connect the special nature of the R^4 term to the U(1) anomaly of pure N=4 supergravity.
Cite
@article{arxiv.1202.3692,
title = {An R^4 non-renormalisation theorem in N=4 supergravity},
author = {Piotr Tourkine and Pierre Vanhove},
journal= {arXiv preprint arXiv:1202.3692},
year = {2015}
}
Comments
v2: added comments about one-loop UV divergences. Assorted stylistic corrections. Added references. v3: Eq. III.21 corrected and assorted minor corrections and clarifications. Version to be published. v4: minor corrections. 18 pages. one figure