https://cea.hal.science/cea-01201562Brax, PhilippePhilippeBraxIPHT - Institut de Physique Théorique - UMR CNRS 3681 - CEA - Commissariat à l'énergie atomique et aux énergies alternatives - Université Paris-Saclay - CNRS - Centre National de la Recherche ScientifiqueValageas, PatrickPatrickValageasIPHT - Institut de Physique Théorique - UMR CNRS 3681 - CEA - Commissariat à l'énergie atomique et aux énergies alternatives - Université Paris-Saclay - CNRS - Centre National de la Recherche ScientifiqueThe effective field theory of K-mouflageHAL CCSD2016[PHYS.GRQC] Physics [physics]/General Relativity and Quantum Cosmology [gr-qc][PHYS.HPHE] Physics [physics]/High Energy Physics - Phenomenology [hep-ph]De Laborderie, Emmanuelle2021-02-24 14:11:392023-03-24 14:53:202021-02-24 15:49:05enJournal articleshttps://cea.hal.science/cea-01201562/document10.1088/1475-7516/2016/01/020application/pdf1We describe K-mouflage models of modified gravity using the effective field theory of dark energy. We show how the Lagrangian density $K$ defining the K-mouflage models appears in the effective field theory framework, at both the exact fully nonlinear level and at the quadratic order of the effective action. We find that K-mouflage scenarios only generate the operator $(\delta g^{00}_{(u)})^n$ at each order $n$. We also reverse engineer K-mouflage models by reconstructing the whole effective field theory, and the full cosmological behaviour, from two functions of the Jordan-frame scale factor in a tomographic manner. This parameterisation is directly related to the implementation of the K-mouflage screening mechanism: screening occurs when $ K'$ is large in a dense environment such as the deep matter and radiation eras. In this way, K-mouflage can be easily implemented as a calculable subclass of models described by the effective field theory of dark energy which could be probed by future surveys.