Related papers: CP-violating inflation and its cosmological imprin…
In this report we construct a phenomenological model in which the time variation of the fine structure constant, $\alpha$, is induced by a parity and charge-parity (PCP) violating interaction. Such a PCP violation in the photon sector has a…
We present a model of inflation where the inflaton is accommodated as a phantom field which exhibits an initial transient pole behavior and then decays into a quintessence field which is responsible for a radiation era. We must stress that…
We investigate the recently proposed class of chaotic inflation models in supergravity with an arbitrary inflaton potential. These models are extended to include matter fields in the visible sector and we employ a mechanism of SUSY breaking…
We study an extension of the Standard Model (SM) in which two copies of the SM Higgs doublet are added to the scalar sector. These extra doublets do not develop a vacuum expectation value, hence, they are \textit{inert}. This essentially…
We investigate the possibility of using the only known fundamental scalar, the Higgs, as an inflaton with minimal coupling to gravity. The peculiar appearance of a plateau or a false vacuum in the renormalised effective scalar potential…
In the vanilla type-I seesaw leptogenesis scenario, CP violation required to generate the lepton asymmetries in the heavy Majorana neutrino decays stem from complex Dirac-type Yukawa couplings. In this paper we explore the case in which…
In this paper, we consider a model of tachyon with a non-minimal coupling to gravity and study its cosmological effects. Regarding inflation we will show that for a specific coupling of tachyon to gravity this model satisfies observations…
We consider gravitationally induced corrections to inflaton potentials driven by supersymmetry breaking in a five-dimensional supergravity, compactified on a $ S_1/Z_2 $ orbifold. The supersymmetry breaking takes place on the hidden brane…
It is shown that the mechanism of spontaneous symmetry breaking provides not only a mechanism for giving mass to the bosons and the fermions, but also a mechanism for generating CP-phase of the bosons and the fermions. A two-Higgs doublet…
The anomalous dimuon charge asymmetry reported by the D0 Collaboration may be due to the tree-level exchange of some spin-0 particles that mediate CP violation in B_s-\bar{B}_s meson mixing. We show that for a range of couplings and masses,…
In this talk, I shall focus on theories beyond the Standard Model which predict massive neutrinos. Hybrid inflation emerges naturally in these theories: the slow-rolling inflaton field is a gauge singlet which couples with a GUT Higgs field…
We have investigated a number of GUT models for the possibility that their Higgs fields might be responsible for inflation in the early universe. In addition to models having an intrinsic Planck mass parameter, we have entertained…
SUSY CP problem in the gauge mediation supersymmetry breaking model is reconsidered. We pay particular attention to two sources of CP violating phases whose effects were not seriously studied before; one is the effect of the breaking of the…
The CP-violating effects are studied in the electron-positron annihilation to produce $t\bar{t}$ pair within the Model-III of the two-Higgs-doublet extensions, which allows flavor changing neutral currents via Higgs exchanges. Complete…
The Standard Model (SM) of particle physics is a big success. However, it lacks explanations for cosmic inflation, the matter-anti-matter asymmetry of the Universe, dark matter, neutrino oscillations, and the feebleness of CP violation in…
The discovery of Higgs mechanism within the context of spontaneous symmetry breaking has offered a new perspective on the early time cosmic inflation and also on the relationship between elementary particles and dark energy, believed to…
In loop quantum cosmology, the universe avoids a big bang singularity and undergoes an early and short super-inflation phase. During super-inflation, non-perturbative quantum corrections to the dynamics drive an inflaton field up its…
We unify one of the most widely studied frameworks to explain the hierarchical structure of the flavor sector in the Standard Model, the Froggatt-Nielsen mechanism, with cosmic inflation. We propose that the complex scalar field, the…
We consider an additional fine-tuning problem which afflicts scalar-driven models of inflation. The problem is that successful reheating requires the inflaton be coupled to ordinary matter, and quantum fluctuations of this matter induces…
We consider CP violating effects in the decays $\tau\rightarrow (3\pi)\nu_\tau$ where both the ${\rm J}^{\rm P}=1^+$ resonance, $a_1$, and ${\rm J}^{\rm P}=0^-$ resonance, $\pi^\prime$, can contribute. The interference between the $a_1$ and…