118 citations · 387 across the 13 of their papers we have counts for
13 papers
Quadratic gravity potentials in de Sitter spacetime from Feynman diagrams
Renata Ferrero, Chris Ripken
We employ a manifestly covariant formalism to compute the tree-level amputated Green's function of non-minimally coupled scalar fields in quadratic gravity in a de Sitter backgroun…
Form Factors in Asymptotically Safe Quantum Gravity
Benjamin Knorr, Chris Ripken, Frank Saueressig
Asymptotic Safety implies that observables including scattering amplitudes remain finite at the highest energy scales. Traditionally, this feature is connected to an interacting fi…
Cartographing gravity-mediated scattering amplitudes: scalars and photons
Benjamin Knorr, Samuel Pirlo, Chris Ripken +1
The effective action includes all quantum corrections arising in a given quantum field theory. Thus it serves as a powerful generating functional from which quantum-corrected scatt…
De Sitter scattering amplitudes in the Born approximation
Renata Ferrero, Chris Ripken
We present a covariant framework to compute scattering amplitudes and potentials in a de Sitter background. In this setting, we compute the potential of a graviton-mediated scatter…
Form Factors in Quantum Gravity - contrasting non-local, ghost-free gravity and Asymptotic Safety
Benjamin Knorr, Chris Ripken, Frank Saueressig
Form factors constitute the key building block when organising the gravitational dynamics in terms of a curvature expansion. They generalise the concept of momentum-dependent coupl…
Scattering amplitudes in affine gravity
Benjamin Knorr, Chris Ripken
Affine gravity is a connection-based formulation of gravity that does not involve a metric. After a review of basic properties of affine gravity, we compute the tree-level scatteri…