Constraints on Tree-Level Higher Order Gravitational Couplings in Superstring Theory

Oct, 2009
4 pages
Published in:
  • Phys.Rev.Lett. 106 (2011) 111601
e-Print:
Report number:
  • MPP-2009-158

Citations per year

2009201320172021202401234567
Abstract: (arXiv)
We consider the scattering amplitudes of five and six gravitons at tree-level in superstring theory. Their power series expansions in the Regge slope alpha' are analyzed through the order alpha'^8 showing some interesting constraints on higher order gravitational couplings in the effective superstring action like the absence of R^5 terms. Furthermore, some transcendentality constraints on the coefficients of the non-vanishing couplings are observed: the absence of zeta values of even weight through the order alpha'^8 like the absence of zeta(2) zeta(3) R^6 terms. Our analysis is valid for any superstring background in any space-time dimension, which allows for a conformal field theory description.
Note:
  • 4 pages, RevTeX 4.1/ v2: Results and discussion extended by the order alpha'^8. Again, no even zeta values occur at this order excluding curvature contact terms with MZV coefficients zeta(8), zeta(2) zeta(3)^2 and zeta(5,3), respectively/ v3: streamlined and final version to appear in Physical Review Letters
  • 04.50.Gh
  • 04.60.Cf
  • 11.25.-w
  • gravitation: coupling
  • gravitation: higher-order
  • superstring: action
  • tree approximation
  • scattering amplitude
  • space-time: any-dimensional
  • Einstein equation