Three-point Functions in Duality-Invariant Higher-Derivative Gravity

TL;DR

This paper computes on-shell three-point functions in a duality-invariant higher-derivative gravity theory, revealing a factorization pattern and specific interactions up to second order in ' with implications for string theory amplitudes.

Contribution

It provides the first all-orders computation of three-point functions in doubled -geometry, highlighting a universal factorization pattern and the absence of Gauss-Bonnet terms.

Findings

Amplitudes factorize similarly to bosonic and heterotic theories.

Contains Riemann-cubed interaction at second order in '.

No Gauss-Bonnet term present.

Abstract

Doubled $\alpha'$-geometry is the simplest higher-derivative gravitational theory with exact global duality symmetry. We use the double metric formulation of this theory to compute on-shell three-point functions to all orders in $\alpha'$. A simple pattern emerges when comparing with the analogous bosonic and heterotic three-point functions. As in these theories, the amplitudes factorize. The theory has no Gauss-Bonnet term, but contains a Riemann-cubed interaction to second order in $\alpha'$.