184 citations · 651 across the 16 of their papers we have counts for
15 papers · 1 filter
Cosmology and the classical limit of the S-matrix
Katsuki Aoki, Andrea Cristofoli
We investigate the relationships between classical observables in cosmology and the classical limit of quantum scattering amplitudes. We first look at the relation between Bogoliub…
Scattering amplitudes for self-force
Tim Adamo, Andrea Cristofoli, Anton Ilderton +1
The self-force expansion allows the study of deviations from geodesic motion due to the emission of radiation and its consequent back-reaction. We investigate this scheme within th…
Large Gauge Effects and the Structure of Amplitudes
Andrea Cristofoli, Asaad Elkhidir, Anton Ilderton +1
We show that large gauge transformations modify the structure of momentum conservation leading to non-vanishing three-point amplitudes in a simple toy model of a gravitational wave…
All order gravitational waveforms from scattering amplitudes
Tim Adamo, Andrea Cristofoli, Anton Ilderton +1
Waveforms are classical observables associated with any radiative physical process. Using scattering amplitudes, these are usually computed in a weak-field regime to some finite or…
The ultrarelativistic limit of Kerr
Tim Adamo, Andrea Cristofoli, Piotr Tourkine
The massless (or ultrarelativistic) limit of a Schwarzschild black hole with fixed energy was determined long ago in the form of the Aichelburg-Sexl shockwave, but the status of th…
Classical physics from amplitudes on curved backgrounds
Tim Adamo, Andrea Cristofoli, Anton Ilderton
We generalise the Kosower-Maybee-O'Connell (KMOC) formalism relating classical observables and scattering amplitudes to curved backgrounds. We show how to compute the final semicla…
Eikonal amplitudes from curved backgrounds
Tim Adamo, Andrea Cristofoli, Piotr Tourkine
Eikonal exponentiation in QFT describes the emergence of classical physics at long distances in terms of a non-trivial resummation of infinitely many diagrams. Long ago, 't Hooft p…
The Uncertainty Principle and Classical Amplitudes
Andrea Cristofoli, Riccardo Gonzo, Nathan Moynihan +4
We study the variance in the measurement of observables during scattering events, as computed using amplitudes. The classical regime, characterised by negligible uncertainty, emerg…
Waveforms from Amplitudes
Andrea Cristofoli, Riccardo Gonzo, David A. Kosower +1
We show how to compute classical wave observables using quantum scattering amplitudes. We discuss observables both with incoming and with outgoing waves. The required classical lim…
Gravitational shock waves and scattering amplitudes
Andrea Cristofoli
We study gravitational shock waves using scattering amplitude techniques. After first reviewing the derivation in General Relativity as an ultrarelativistic boost of a Schwarzschil…
Second-order Post-Minkowskian scattering in arbitrary dimensions
Andrea Cristofoli, Poul H. Damgaard, Paolo Di Vecchia +1
We extract the long-range gravitational potential between two scalar particles with arbitrary masses from the two-to-two elastic scattering amplitude at 2nd Post-Minkowskian order…
Post-Minkowskian Scattering Angle in Einstein Gravity
N. E. J. Bjerrum-Bohr, Andrea Cristofoli, Poul H. Damgaard
Using the implicit function theorem we demonstrate that solutions to the classical part of the relativistic Lippmann-Schwinger equation are in one-to-one correspondence with those…
Scalar-Graviton Amplitudes
N. E. J. Bjerrum-Bohr, Andrea Cristofoli, Poul H. Damgaard +1
Using the CHY-formalism and its extension to a double cover we provide covariant expressions for tree-level amplitudes with two massive scalar legs and an arbitrary number of gravi…
Post-Minkowskian Hamiltonians in Modified Theories of Gravity
Andrea Cristofoli
The aim of this note is to describe the computation of post-Minkwoskian Hamiltonians in modified theories of gravity. Exploiting a recent relation between amplitudes of massive sca…
On Post-Minkowskian Hamiltonians in General Relativity
Andrea Cristofoli, N. E. J. Bjerrum-Bohr, Poul H. Damgaard +1
We describe the computation of post-Minkowskian Hamiltonians in General Relativity from scattering amplitudes. Using a relativistic Lippmann-Schwinger equation, we relate perturbat…