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 …

A bstract We show that color-kinematics duality is a manifest property of the equations of
motion governing currents and field strengths. For the nonlinear sigma model (NLSM), this …

We derive bounds on couplings in the standard model effective field theory (SMEFT) as a
consequence of causality and the analytic structure of scattering amplitudes. In the SMEFT …

A bstract We apply on-shell methods to the bottom-up construction of electroweak
amplitudes, allowing for both renormalizable and non-renormalizable interactions. We use …

A bstract We derive a universal soft theorem for every scattering amplitude with at least one
massless particle in an arbitrary theory of scalars. Our results follow from the geometry of …

A bstract The soft bootstrap is an on-shell method to constrain the landscape of effective field
theories (EFTs) of massless particles via the consistency of the low-energy S-matrix. Given …

A bstract Color-kinematics duality in the adjoint has proven key to the relationship between
gauge and gravity theory scattering amplitude predictions. In recent work, we demonstrated …

A bstract We present a map between the tree-level Standard Model Effective Theory
(SMEFT) in the Warsaw basis and massive on-shell amplitudes. As a first step, we focus on …

We derive a new soft theorem that corresponds to the spontaneous breaking of Lorentz
boosts. This is motivated by the dynamics of inflation in the subhorizon (flat-space) limit …

We establish a simple formula for the minimal dimension of operators leading to any helicity
amplitude. It eases the systematic enumeration of independent operators from the …