Item

Abstract

The puzzling lightness of the Higgs boson, when one considers the Standard Model as an effective field theory to be completed, has driven much of the particle physics research over the last decades. Two paradigms have emerged as solutions to this puzzle: supersymmetry and compositeness. The absence of signals at the LHC pushes these solutions into regions of evermore fine-tuning. We present three novel approaches aimed at explaining the absence of these signatures. The first one, exploiting the large contribution of the top Yukawa to the Higgs mass, proposes a non-symmetry-based solution in which the top Yukawa only obtains its sizeable value in the IR and we discuss its new phenomenological signatures. Secondly, we present a minimal model of 5D warped gauge-Higgs grand unification, study its compelling flavor structure and analyse the resulting constraints. Although these constraints push the model to high scales, additional scalars that reside below the Kaluza-Klein states may provide accessible experimental signatures. Finally, we provide a novel model of composite Higgs generating the Higgs potential at subleading order using a remarkable property of group representations. The model is analysed and can evade existing bounds with little tuning. New light particles are predicted with unusual decays in which naturalness at the LHC may be hidden.