Related papers: Can thermal inflation solve the monopole problem ?
Axions in the Peccei-Quinn (PQ) mechanism provide a promising solution to the strong CP problem in the standard model of particle physics. Coherently generated PQ scalar fields could dominate the energy density in the early Universe and…
We present a new solution to the hierarchy problem, where the Higgs mass is at its observed electroweak value because such a patch inflates the most in the early universe. If the Higgs mass depends on a field undergoing quantum fluctuations…
Inflation is nowadays a well-established paradigm consistent with all the observations. The precise nature of the inflaton is however unknown and its role could be played by any candidate able to imitate a scalar condensate in the slow-roll…
We briefly review several Higgs inflation models and discuss their cosmological implications. We first classify the inflation models according to the predicted value of the tensor-to-scalar ratio: (i) $r = {\cal O}(0.01-0.1)$, (ii) $r =…
Higgs inflation can occur if the Standard Model (SM) is a self-consistent effective field theory up to inflationary scale. This leads to a lower bound on the Higgs boson mass, $M_h \geq M_{\text{crit}}$. If $M_h$ is more than a few hundreds…
We construct a two-stage inflationary model which can accommodate early inflation at a scale $\Lambda_1$ as well as a second stage of inflation at $\Lambda_2$ with a single scalar field $\phi$. We use a symmetric potential, valid in a…
We investigate an inflation model with the inflaton being identified with a Higgs boson responsible for the breaking of U(1)B-L symmetry. We show that supersymmetry must remain a good symmetry at scales one order of magnitude below the…
We show that it is possible to obtain inflation and also solve the cosmological constant problem. The theory is invariant under changes of the Lagrangian density $L$ to $L+const$. Then the constant part of a scalar field potential $V$…
We discuss inflation in models with large extra dimensions, driven by a bulk scalar field. The brane inflaton is then a single effective field, obtained from the bulk scalar field by scaling. The self interaction terms of the effective…
We argue that an extension of the Minimal Supersymmetric Standard Model that gives rise to viable thermal inflation, and so does not suffer from a Polonyi/moduli problem, should contain right-handed neutrinos which acquire their masses due…
Thermal inflation was proposed as a mechanism to dilute the density of cosmological moduli. Thermal inflation is driven by a complex scalar field possessing a large vacuum expectation value and a very flat potential, called a `flaton'. Such…
Magnetic monopoles are a long-standing prediction of Grand Unified Theories, yet their efficient production in early universe phase transitions would lead to a monopole abundance that far exceeds observational limits. The standard solution…
The model of fresh inflation with increasing cosmological parameter provides sufficient e-folds to solve the flatness/horizon problem and the density fluctuations agree with experimental values. In this model the temperature increases…
We reconsider the problems of cosmological inflation in effective supergravity theories. A singlet field in a hidden sector is demonstrated to yield an acceptable inflationary potential, without fine tuning. In the simplest such model, the…
The simplest two-field completion of natural inflation has a regime in which both fields are active and in which its predictions are within the Planck 1-$\sigma$ confidence contour. We show this for the original model of natural inflation,…
We study the post-inflationary dynamics of the Standard Model Higgs and a real singlet scalar $s$, coupled together through a renormalizable coupling $\lambda_{sh}h^2s^2$, in a $Z_2$ symmetric model that may explain the observed dark matter…
We present an effective model where the inflaton is a relaxion that scans the Higgs mass and sets it at the weak scale. The dynamics consist of a long epoch in which inflation is due to the shallow slope of the potential, followed by a few…
We analyse one-loop radiative corrections to the inflationary potential in the theory, where inflation is driven by the Standard Model Higgs field. We show that inflation is possible provided the Higgs mass m_H lies in the interval…
We consider models of chaotic inflation driven by the real parts of a conjugate pair of Higgs superfields involved in the spontaneous breaking of a grand unification symmetry at a scale assuming its supersymmetric value. We combine a…
We consider hybrid inflation in the braneworld scenario. In particular, we consider inflation in global supersymmetry with the D-terms in the scalar potential for the inflaton field to be the dominant ones (D-term inflation). We find that…