Related papers: Softening the Naturalness Problem
The relaxion mechanism provides a potentially elegant solution to the hierarchy problem without resorting to anthropic or other fine-tuning arguments. This mechanism introduces an axion-like field, dubbed the relaxion, whose expectation…
In the contest of supersymmetric extensions of the Standard Model, we consider a spectrum in which the lightest Higgs boson has mass between 200 and 300 GeV and the first two generations of squarks have masses above 20 TeV, considering the…
The Higgs mechanism predicts, apart from the existence of a new scalar boson, the presence of a constant Higgs field that permeates all of space. The vacuum expectation value (VEV) of this field is affected by quantum corrections which are…
We discuss how naturalness predicts the scale of new physics. Two conditions on the scale are considered. The first is the more conservative condition due to Veltman (Acta Phys. Polon. B 12, 437 (1981)). It requires that radiative…
The triviality and vacuum stability bounds on the Higgs-boson mass are revisited in the presence of new interactions parameterized in a model-independent way by an effective lagrangian. When the scale of new physics is below 50 TeV the…
We consider the extension of the Standard Model by a complex scalar triplet field, which occurs naturally in several models of leptogenesis and see-saw mechanism for neutrino mass generation, in the context of ameliorating the fine-tuning…
We adopt a bottom-up Effective Field Theory (EFT) approach to derive a model-independent Veltman condition to cancel the quadratic divergences in the Higgs mass. We show using the equivalence theorem that all deviations in the Higgs…
We present `twin Higgs models', simple realizations of the Higgs as a pseudo-Goldstone boson that protect the weak scale from radiative corrections up to scales of order 5 - 10 TeV. In the ultra-violet these theories have a discrete…
It is widely believed that quadratic divergences severely restrict natural constructions of particle physics models beyond the standard model (SM). Supersymmetry provides a beautiful solution, but the recent LHC experiments have excluded…
Naturalness demands that the quadratic divergence of the one-loop top contribution to the Higgs mass be cancelled at a scale below 1 TeV. This can be achieved by introducing a fermionic (spin-1/2) top partner, as in, for example, Little…
If weak scale supersymmetry (SUSY) is to somehow explain the radiative stability of the Higgs boson mass, it is likely that non-minimal variants of SUSY models should be considered. Under the assumption that the dark matter of the universe…
A vector-like colorless fermion doublet and a singlet added to the Standard Model allow a consistent interpretation of dark matter in terms of the lightest neutral particle, as they may help in obtaining successful gauge coupling…
Extending the spacetime symmetries of standard model (SM) by scale invariance (SI) may address the Higgs naturalness problem. In this article we attempt to embed accidental dark matter (DM) into SISM, requiring that the symmetry protecting…
We discuss two novel possibilities in Higgs physics. The first is that, by adding a real Higgs triplet to the Standard Model, it is possible for the lightest Higgs boson to be as heavy as 500 GeV without any fine tuning. The second,…
First we review Veltman's suggestion to attack the naturalness problem in the Standard model by requiring absence of quadratic divergences and the resulting mass formula. Then we emphasise the influence of Veltman's suggestion in…
The idea of reduction of couplings provides a systematic procedure to search for relations among seemingly unrelated parameters of a renormalizable theory. As a consequence, such reduced theories exhibit more constrained parameter spaces.…
It is known that the recently reported shift of the W boson mass can be easily explained by an $SU(2)_L$ triplet Higgs boson with a zero hypercharge if it obtains a vacuum expectation value (VEV) of $O(1)$ GeV. Surprisingly, the addition of…
The naturalness principle has long guided efforts to understand physics beyond the Standard Model, with the hierarchy problem as the central issue. We revisit the role of quantum corrections in the fine-tuning of the low-energy effective…
We construct a little Higgs model using a simple global symmetry group SU(9) spontaneously broken to SU(8). The electroweak interactions are extended to SU(3)xU(1) and embedded in SU(9). At the electroweak scale, our model is a two…
We present a model of electroweak symmetry breaking in which the Higgs boson is a pseudo-Nambu-Goldstone boson. By embedding the standard model SU(2) x U(1) into an SU(4) x U(1) gauge group, one-loop quadratic divergences to the Higgs mass…