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 We introduce a bosonic ambitwistor string theory in AdS space. Even though the
theory is anomalous at the quantum level, one can nevertheless use it in the classical limit to …

A bstract In this paper, we develop an improved method for directly calculating double-copy-
compatible tree numerators in (super-) Yang-Mills and Yang-Mills-scalar theories. Our new …

Starting with Witten's twistor string, chiral string theories have emerged that describe field
theory amplitudes without the towers of massive states of conventional strings. These …

A bstract We derive from ambitwistor strings new formulae for two-loop scattering amplitudes
in supergravity and super-Yang-Mills theory, with any number of particles. We start by …

A bstract We present new and explicit formulae for the one-loop integrands of scattering
amplitudes in non-supersymmetric gauge theory and gravity, valid for any number of …

We present an integration-by-parts reduction of any massless tree-level string correlator to
an equivalence class of logarithmic functions, which can be used to define a field-theory …

A bstract We consider D-dimensional amplitudes in R 2 gravities (conformal gravity in D= 4)
and in the recently introduced (DF) 2 gauge theory, from the perspective of the CHY …

A bstract We further elaborate on the general construction proposed in [1], which connects,
via tree-level double copy, massless string amplitudes with color-ordered QFT amplitudes …

A bstract The scattering equation formalism for scattering amplitudes, and its stringy
incarnation, the ambitwistor string, remains a mysterious construction. In this paper, we …