Dark Energy and Modified gravity
Covariant Galileonic Higgs Cosmology
Matthew Hull
Kazuya Koyama (ICG Portsmouth), Gianmassimo Tasinato (Swansea)
Institute of Cosmology and Gravitation, Portsmouth
Vector Galileons are vector fields that have scalar Galileons as their longitudinal modes. They belong to a general, nonlinear, higher derivative extension of the Proca system. Due to this close relation with scalar Galileons, the covariant theories possess interesting cosmological applications such as self-acceleration and the ability to screen via a Vainshtein mechanism. Such properties lends support to these theories forming an alternative explanation for the late time cosmic expansion. I will introduce a nonlinear, higher derivative extension to the Higgs mechanism that generates vector Galleons spontaneously. I will further discuss how the covariantisation of this model is made nontrivial due to the presence of higher derivatives and how it can be achieved via the use of non-minimal derivative couplings with curvature tensors. We find that the covariant theory can be seen as a higher order extension to Higgs G-inflation and therefore the range of possible cosmological applications is extended beyond the late time cosmic expansion of scalar and vector Galileons to include early universe physics.


13:30 - 15:00
BS - Lecture Theatre A25 (121)