Related papers: The hierarchy problem and the cosmological constan…
A remarkable prediction of the Standard Model is that, in the absence of corrections lifting the energy density, the Higgs potential becomes negative at large field values. If the Higgs field samples this part of the potential during…
We study the nonperturbative dynamics of the Standard Model (SM) after inflation, in the regime where the SM is decoupled from (or weakly coupled to) the inflationary sector. We use classical lattice simulations in an expanding box in (3+1)…
The measured masses of the Higgs boson and top quark indicate that the effective potential of the standard model either develops an unstable electroweak vacuum or stands stable all the way up to the Planck scale. In the latter case in which…
A large value of the cosmological constant (CC) is induced in the Standard Model (SM) of Elementary Particle Physics because of Spontaneous Symmetry Breaking. To provide a small value of the observable CC one has to introduce the vacuum…
We consider a simple extension of the Standard Model Higgs inflation with one new real scalar field which preserves unitarity up to the Planck scale. The new scalar field (called sigma) completes in the ultraviolet the theory of Higgs…
In the Standard Model (SM), the Higgs mass around 125 GeV implies that the electroweak vacuum is metastable since the quartic Higgs coupling turns negative at high energies. I point out that a tiny mixing of the Higgs with a heavy singlet…
String theory has no parameter except the string scale $M_S$, so the Planck scale $M_\text{Pl}$, the supersymmetry-breaking scale, the EW scale $m_\text{EW}$ as well as the vacuum energy density (cosmological constant) $\Lambda$ are to be…
We argue that the discrepancy between the Planck mass scale and the observed value of the cosmological constant can be largely attenuated if those quantities are understood as a result of effective, and thus scale-dependent, couplings. We…
We study gauge hierarchy problem of the Standard Model (SM) not by introducing new physics at the electroweak scale but by utilizing gravitational frames, frames generated by conformal transformations, as a renormalization medium. The…
The analysis of theories with non-minimal coupling of Higgs field to gravity revealed that they enter into strong coupling regime above certain Higgs-dependent cutoff, which may be considerably below the Planck scale. Assuming that the…
The lore paradigm for solving so-called horizon and flatness problems in cosmology is the primordial inflation. Plethora of inflationary models have been built in last decades and first experimental probes seem to appear in favor of the…
The observed Higgs mass indicates that the Standard Model can be valid up to near the Planck scale $M_\text{P}$. Within this framework, it is important to examine how little modification is necessary to fit the recent experimental results…
We have considered a cosmological model with a cosmological constant of the form $\Lambda=3\alpha\frac{\dot R^2}{R^2}+\bt\frac{\ddot R}{R} \alpha, \bt=\rm const.$ The cosmological constant is found to decrease as $t^{-2}$ and the rate of…
In this article the stability of the Standard Model (SM) vacuum in the presence of radiative corrections and for a Higgs boson with a mass in the vicinity of 125 GeV is discussed. The central piece in this discussion will be the Higgs…
We introduce a new approach to the Higgs naturalness problem, where the value of the Higgs mass is tied to cosmic stability and the possibility of a large observable Universe. The Higgs mixes with the dilaton of a CFT sector whose true…
We critically examine the recent claim that the Standard Model Higgs boson ${\cal H}$ could drive inflation in agreement with observations if $|{\cal H}|^2$ has a strong coupling $\xi\sim 10^4$ to the Ricci curvature scalar. We first show…
The possibility that the Standard Model (SM) is valid up to the Planck scale $M_P$, i.e. that new physics occurs only around $M_P$, is nowadays largely explored. For a metastable EW vacuum, we show that new physics interactions can have a…
The Lee-Wick (LW) Standard Model (SM) offers a new solution to the hierarchy problem. We discuss, using effective potential techniques, its peculiar ultraviolet (UV) behaviour. We show how quadratic divergences in the Higgs mass Mh cancel…
We discuss applications of perturbative quantum gravity in the theory of very early quantum Universe and quantum cosmology. Consistency of the theoretical formalism for quantum effects of matter and correspondence with observational status…
We present a class of non-supersymmetric models in which so-called critical Higgs inflation ($\xi<100$) naturally can be realized without using specific values for Higgs and top quark masses. In these scenarios, the Standard Model (SM)…