This review describes the duality between color and kinematics and its applications, with the
aim of gaining a deeper understanding of the perturbative structure of gauge and gravity …

We give a comprehensive review of recent developments on using the pure spinor
formalism to compute massless superstring scattering amplitudes at tree level. The main …

The double copy is, in essence, a map between scattering amplitudes in a broad variety of
familiar field and string theories. In addition to the mathematically rich intrinsic structure, it …

A bstract The search for a theory of the S-Matrix over the past five decades has revealed
surprising geometric structures underlying scattering amplitudes ranging from the string …

We show that the BRST Lagrangian double copy construction of supergravity as the
'square'of Yang–Mills theory finds a natural interpretation in terms of homotopy algebras. We …

A bstract We systematically explore the space of scalar effective field theories (EFTs)
consistent with a Lorentz invariant and local S-matrix. To do so we define an EFT …

A bstract Many gauge theories possess a hidden duality between color and kinematics in
their on-shell scattering amplitudes. An open problem is to formulate an off-shell realization …

We propose a world sheet formula for tree-level correlation functions describing a scalar
field with arbitrary mass and quartic self-interaction in de Sitter space, which is a simple …

We use Picard-Lefschetz theory to prove a new formula for intersection numbers of twisted
cocycles associated with a given arrangement of hyperplanes. In a special case when this …

A bstract Recent works have explored how scattering amplitudes in quantum self-dual Yang-
Mills theory and self-dual gravity can be interpreted as resulting from an anomaly, as first …