1212.0394 (Indrani Chakraborty et al.)

Controlling the fine-tuning problem with singlet scalar dark matter    [PDF]

Indrani Chakraborty, Anirban Kundu

Assuming that no other conventional new physics is found immediately at the LHC, we investigate how just the existence of dark matter points towards a solution of the hierarchy problem of the Higgs mass. We show that to ameliorate the fine-tuning problem, one needs to introduce more scalar degrees of freedom which may act as cold dark matter, because the constraints on the scalar potential disfavor any mixing between the new scalar(s) with the SM doublet. Furthermore, the fine-tuning problem of the new scalars necessitates the introduction of vector-like fermions. Thus, singlet scalar(s) and vector fermions are minimal enhancements over the Standard Model to alleviate the fine-tuning problem. We also show that the model predicts Landau poles for all the scalar couplings, whose positions depend only on the number of such singlets. Thus, introduction of some new physics at that scale becomes inevitable.

View original: http://arxiv.org/abs/1212.0394