activity
20172020
collaborators

6 papers

gr-qc2020

Parameterised post-Newtonian formalism for the effective field theory of dark energy via screened reconstructed Horndeski theories

Cyril Renevey, Joe Kennedy, Lucas Lombriser

We bring together two popular formalisms which generically parameterise deviations from General Relativity on astrophysical and cosmological scales, namely the parameterised post-N…

gr-qc2020

Positivity bounds on reconstructed Horndeski models

Joe Kennedy, Lucas Lombriser

Positivity bounds provide conditions that a consistent UV-completion exists for a quantum field theory. We examine their application to Horndeski gravity models reconstructed from…

gr-qc2019

Screening and degenerate kinetic self-acceleration from the nonlinear freedom of reconstructed Horndeski theories

Joe Kennedy, Lucas Lombriser, Andy Taylor

We have previously presented a reconstruction of Horndeski scalar-tensor theories from linear cosmological observables. It includes free nonlinear terms which can be added onto the…

astro-ph.CO2018

Inherently stable effective field theory for dark energy and modified gravity

Lucas Lombriser, Charles Dalang, Joe Kennedy +1

The growing wealth of cosmological observations places increasingly more stringent constraints on dark energy and alternative gravity models. Particularly successful in efficiently…

astro-ph.CO2018

Reconstructing Horndeski theories from phenomenological modified gravity and dark energy models on cosmological scales

Joe Kennedy, Lucas Lombriser, Andy Taylor

Recently we have derived a set of mapping relations that enables the reconstruction of the family of Horndeski scalar-tensor theories which reproduce the background dynamics and li…

gr-qc2017

Reconstructing Horndeski models from the effective field theory of dark energy

Joe Kennedy, Lucas Lombriser, Andy Taylor

Studying the effects of dark energy and modified gravity on cosmological scales has led to a great number of physical models being developed. The effective field theory (EFT) of co…