YOUNGST@RS - Loop-the-Loop: Feynman Calculus and its Applications to Gravity and Particle Physics

Session

Scattering Amplitudes in Gravity

13 Nov 2024, 10:30

12. Solving Einstein equation using recursions

Kanghoon Lee

13/11/2024, 10:30

I’ll discuss solving the perturbative Einstein equation using recursions and the iterative structure of the loop integrals. Using this method, I’ll show how to derive the Schwarzschild metric to all orders in Newton's constant. It is a first all-order perturbative computation in Einstein gravity with a matter source. I'll also discuss the generalization to the binary black holes.

13. Schwarzschild geodesics from Scattering Amplitudes to all orders in G

Stavros Mougiakakos

13/11/2024, 11:00

In this talk, we will discuss the application of the EFT framework to the study of the gravitational two-body problem in the Self-Force (SF) expansion. After reviewing some basic ingredients of worldline EFT formalism, we will introduce an SF-EFT framework. Finally, a complete computation at 0SF starting from flat background will be presented, resulting from an explicit resummation of infinite...

14. Effective field theory in a mass ratio expansion

Nabha Shah

13/11/2024, 11:30

Field theoretic approaches, perfectly tailored for computations perturbative in Newton’s constant, have had great success in producing state-of-the-art results for the gravitational two-body problem. On the other hand, metrics such as the Schwarzschild metric and geodesic trajectories in these spacetimes carry information to all orders in the gravitational constant and can be interpreted as...

15. How to compute Post-Minkowskian integrals

Gregor Kälin

13/11/2024, 13:30

The Post-Minkowskian EFT (PMEFT) description of the gravitational two-body problem features a set of Feynman-like integrals that differ from those usually seen in particle physics. These defining properties require a retooling of the highly developed particle physics integration machinery. Some of these differences make your life difficult while others allow you to cut some corners or...

16. Analytic Waveforms from Scattering Amplitudes

Stefano De Angelis

13/11/2024, 14:00

The central theme of the talk is the direct computation of gravitational waveform produced by the scattering of two black holes through scattering-amplitude methods in the post-Minkowskian expansion. I will discuss how the results of Scattering Amplitude computations match the analytic results from General Relativity in the small-velocity expansion and a novel computational strategy to obtain...

17. Black hole scattering at fifth Post-Minkowskian and first self force order

Benjamin Sauer

13/11/2024, 14:30

I will discuss the calculation of the impulse at fifth Post Minkowksian order at first self force order including both conservative and dissipative effects in the Worldline Quantum Field Theory formalism. The difficulty in this 4 loop calculation lies in the appearing Feynman integrals. On the one hand the IBP reduction is a major technical obstacle to overcome. On the other hand periods over...

18. Differential Equations for Cosmological Correlators

Hayden Lee

13/11/2024, 15:30

In this talk, I will discuss differential equations for cosmological correlators in FRW spacetimes. These correlators have an integral representation in boundary kinematic space, which can be obtained from a finite set of master integrals that satisfy interesting differential equations. I will describe a graphical representation of these differential equations and show how they can be derived...

19. A physical basis for cosmological correlators from cuts

Shounak De

13/11/2024, 16:00

Significant progress has been made in our understanding of the analytic structure of FRW wavefunction coefficients, facilitated by the development of efficient algorithms to derive the differential equations (DEQ) they satisfy. Moreover, recent findings indicate that the twisted cohomology framework tied to the hyperplane arrangement of these twisted integrals overestimates the number of...

20. On the loop structure of the wavefunction of the universe

Francisco Vazão

13/11/2024, 16:30

In this talk we discuss a systematic analysis to extract the asymptotic behaviour of perturbative contributions to observables in power-law FRW cosmologies, indistinctly the cosmological wavefunction and correlators, as well as one loop corrections to the wavefunction. The perturbative contributions to an observable can be expressed as an integral of the canonical function associated to...