Docentföreläsning: The hidden simplicity of scattering amplitudes in gravitational theories

The Department of Physics and Astronomy hereby invites all interested to a docentship lecture in the subject of Theoretical Physics.

Lecturer: Dr. Marco Chiodaroli

Title: The hidden simplicity of scattering amplitudes in gravitational theories

Date: Monday 1st June 2020 at 13:15

Location: 4001 Ångströmlaboratoriet, Polacksbacken (social distancing measures will apply)

Zoom participation via Meeting ID: 610 1503 2843 (

Chairperson: Prof. Maxim Zabzine

Representative of the Docentship Committee: Prof. Stephan Pomp

Abstract: Gauge and gravitational theories play fundamentally different roles in our understanding of nature and, superficially, seem to possess completely different properties. However, recent work has revealed surprising connections between these two classes of theories. These connections are manifested through the study of scattering amplitudes, mathematical quantities that encode how particles interact in scattering events. Amplitudes in gauge theory are closely related to observations in particle accelerators. Calculating amplitudes in gravitational theories is a way to check their consistency by asking basic questions on how particles interact.

This lecture will review recent progress in amplitude calculations in a pedagogical way. I will start by providing an introduction to how scattering amplitudes are computed in quantum field theory, with particular attention to modern recursive and unitarity methods that construct amplitudes employing physical building blocks. I will then bring into focus the so-called double-copy construction, which expresses gravity amplitudes in terms of simpler building blocks from gauge theory. I will conclude by discussing applications of double-copy methods to current problems in theoretical and gravitational-wave physics.

The lecture is an obligatory teaching test for those applying for admittance as docent and it should be possible for students and others with basic academic education in the relevant field to follow it. The lecture will last for 45 minutes and afterwards the audience may ask questions. The lecture will be given in English.