Résumé |
Recent conceptual and technical advances have allowed us to delve further than ever before into
the quantum corrections to scattering amplitudes, perhaps nature's most perfect microscopic
structures. Doing so we have uncovered surprisingly powerful relations known as the color-
kinematic duality, and associated double-copy structure, universal to many theories from the
entirely formal to the utterly effective; applicable to processes from pion scattering to cosmic
inflation. Using the color-kinematic duality to construct double-copy amplitudes has tremendous
computational advantages, but manifesting the necessary duality can be challenging at higher
loops. After a gentle introduction to the ideas and tools at the heart of modern multi-loop
integrand construction, I will introduce a new approach that starts from generic gauge-theory
integrands, and applies a universal double-copy procedure to obtain gravity integrands that include
contact terms generated by any single-copy violations of dual Jacobi identities. I will demonstrate
with three-, four- and five-loop examples in maximal supergravity. |