Gravity amplitudes from a Gaussian matrix model

Gravity Amplitudes from n-Space

We identify a hidden GL(n,C) symmetry of the tree level n-point MHV gravity amplitude. Representations of this symmetry reside in an auxiliary n-space whose indices are external particle labels. Spinor helicity variables transform non-linearly under GL(n,C), but linearly under its notable subgroups, the little group and the permutation group Sn. Using GL(n,C) covariant variables, we present a n...

Perturbative Gravity from QCD Amplitudes

We demonstrate that QCD gluon amplitudes can be used to construct a Lagrangian for gravity. This procedure makes use of perturbative ‘squaring’ relations between gravity and gauge theory that follow from string theory. We explicitly carry out the construction for up to five-point interactions and discuss a set of field variables in the Einstein-Hilbert Lagrangian for interpreting the Lagrangian...

Continuum annulus amplitudes from the two-matrix model.

An explicit expression for continuum annulus amplitudes having boundary lengths ℓ 1 and ℓ 2 is obtained from the two-matrix model for the case of the uni-tary series; (p, q) = (m + 1, m). In the limit of vanishing cosmological constant, we find an integral representation of these amplitudes which is reproduced, for the cases of the m = 2 (c = 0) and the m → ∞ (c = 1), by a continuum approach co...

A Recursion Relation for Gravity Amplitudes

Britto, Cachazo and Feng have recently derived a recursion relation for tree-level scattering amplitudes in Yang-Mills. This relation has a bilinear structure inherited from factorisation on multi-particle poles of the scattering amplitudes – a rather generic feature of field theory. Motivated by this, we propose a new recursion relation for scattering amplitudes of gravitons at tree level. Usi...

A Link Representation for Gravity Amplitudes