Kiyoharu Kawana

Landau pole in the Standard Model with weakly interacting scalar fields

Abstract We consider the Standard Model with a new scalar field X which is an n X representation of the SU ( 2 ) L with a hypercharge Y X . The renormalization group running effects on the new scalar quartic coupling constants are evaluated. Even if we set the scalar quartic coupling constants to be zero at the scale of the new scalar field, the coupling constants are induced by the one-loop effect of the weak gauge bosons. Once non-vanishing couplings are generated, the couplings rapidly increase by renormalization group effect of the quartic coupling constant itself. As a result, the Landau pole appears below Planck scale if n X ≥ 4 . We find that the scale of the obtained Landau pole is much lower than that evaluated by solving the one-loop beta function of the gauge coupling constants.

Multiple point principle of the Standard Model with scalar singlet dark matter and right-handed neutrinos

We consider the multiple point principle (MPP) of the Standard Model (SM) with the scalar singlet Dark Matter (DM) and three heavy right-handed neutrinos at the scale where the beta function �� of the effective Higgs self couplingeff becomes zero. We make the two-loop analysis and find that the top quark mass Mt and the Higgs portal couplingare strongly related each other. One of the good points in this model is that the larger Mt (& 171GeV) is allowed. This fact is consistent with the recent experimental value (28) Mt = 173.34 ± 0.76 GeV, which corresponds to the DM mass 769 GeV ≤ mDM ≤ 1053 GeV.

Evidence of the Big Fix

We give an evidence of the Big Fix. The theory of wormholes and multiverse suggests that the parameters of the Standard Model are fixed in such a way that the total entropy at the late stage of the universe is maximized, which we call the maximum entropy principle. In this paper, we discuss how it can be confirmed by the experimental data, and we show that it is indeed true for the Higgs vacuum expectation value vh. We assume that the baryon number is produced by the sphaleron process, and that the current quark masses, the gauge couplings and the Higgs self-coupling are fixed when we vary vh. It turns out that the existence of the atomic nuclei plays a crucial role to maximize the entropy. This is reminiscent of the anthropic principle, however it is required by the fundamental law in our case.

Weak scale from the maximum entropy principle

The theory of multiverse and wormholes suggests that the parameters of the Standard Model are fixed in such a way that the radiation of the S 3 universe at the final stage Srad becomes maximum, which we call the maximum entropy principle. Although it is difficult to confirm this principle generally, for a few parameters of the Standard Model, we can check whether Srad actually becomes maximum at the observed values. In this paper, we regard Srad at the final stage as a function of the weak scale ( the Higgs expectation value ) vh, and show that it becomes maximum around vh = O(300GeV) when the dimensionless couplings in the Standard Model, that is, the Higgs self coupling, the gauge couplings, and the Yukawa couplings are fixed. Roughly speaking, we find that the weak scale is given by vh ∼ T 2 BBN Mply 5 ,

Criticality and inflation of the gauged B – L model

We consider the multiple point principle (MPP) and the inflation of the gauged B-L extension of the Standard Model (SM) with a classical conformality. We examine whether the scalar couplings and their beta functions can become simultaneously zero at

Natural solution to the naturalness problem: The universe does fine-tuning

\Lambda_{\text{MPP}}:=10^{17}

Saddle point inflation in string-inspired theory

GeV by using the two-loop renormalization group equations (RGEs). We find that we can actually realize such a situation and that the parameters of the model are uniquely determined by the MPP. However, as discussed in \cite{Iso:2012jn}, if we want to realize the electroweak symmetry breaking by the radiative B-L symmetry breaking, the self coupling

Reheating-era leptogenesis

\lambda_{\Psi}

Possible explanations for fine-tuning of the universe

of a newly introduced SM singlet complex scalar

A note on graviton exchange in the emergent gravity scenario

\Psi