### Speaker

Dr
Oliver Schlotterer
(AEI Potsdam)

### Description

In this talk we derive the tree-level S-matrix of the effective theory of
Goldstone bosons known as the non-linear sigma model (NLSM) from
string theory. This novel connection relies on a recent realization of tree-level
open-superstring S-matrix predictions as a double copy of super-Yang--Mills theory
with Z-theory --- the collection of putative scalar effective field theories
encoding all the alpha'-dependence of the open superstring.
Here we identify the color-ordered amplitudes of the NLSM as the low-energy
limit of abelian Z-theory. This realization also provides
natural higher-derivative corrections to the NLSM amplitudes arising from
higher powers of alpha' in the abelian Z-theory amplitudes, and through double copy
also to Born--Infeld and Volkov--Akulov theories. The Kleiss--Kuijf
and Bern--Carrasco--Johansson relations obeyed by Z-theory amplitudes thereby
apply to all alpha'-corrections of the NLSM. As such we naturally obtain
a cubic-graph parameterization for the abelian Z-theory predictions
whose kinematic numerators obey the duality between color and kinematics
to all orders in alpha'.

### Primary author

Dr
Oliver Schlotterer
(AEI Potsdam)

### Co-authors

Dr
Carlos Mafra
(University of Southampton)
Dr
John-Joseph Carrasco
(CEA Saclay)