119213797
Tensor to Scalar Ratio in Non-Minimal $\phi^4$ Inflation
We reconsider nonminimal λφ 4 chaotic inflation which includes the gravitational coupling term ξℜφ 2 , where φ denotes a gauge singlet inflaton field and ℜ is the Ricci scalar. For ξ ≫ 1, we require, following recent discussions, that the energy scale λ 1/4mP/√ξ for inflation should not exceed the effective UV cutoff scale m P /ξ, where m P denotes the reduced Planck scale. The predictions for the tensor-to-scalar ratio r and the scalar spectral index n s are found to lie within the Wilkinson Microwave Anisotropy Probe 1-σ bounds for 10 -12 ≲ λ ≲ 10 -4 and 10 -3 ≲ ξ ≲ 10 2 . In contrast, the corresponding predictions of minimal λφ 4 chaotic inflation lie outside the Wilkinson Microwave Anisotropy Probe 2-σ bounds. We also find that r ≳ 0.002, provided the scalar spectral index n s ≥ 0.96. In estimating the lower bound on r, we take into account possible modifications due to quantum corrections of the tree level inflationary potential.
119273809
Higgs inflation, quantum smearing, and the tensor to scalar ratio
In cosmic inflation driven by a scalar gauge singlet field with a tree level Higgs potential, the scalar to tensor ratio r is estimated to be larger than 0.036, provided the scalar spectral index n{sub s{>=}}0.96. We discuss quantum smearing of these predictions arising from the inflaton couplings to other particles such as grand unified theory scalars, and show that these corrections can significantly decrease r. However, for n{sub s{>=}}0.96, we obtain r{>=}0.02 which can be tested by the Planck satellite.
119279940
Running Standard Model Inflation And Type I Seesaw
Several authors have recently argued that a satisfactory inflationary scenario can be implemented in the Standard Model (SM) by introducing a strong non-minimal coupling of the Higgs doublet to gravity. It is shown here that type I seesaw physics containing right handed neutrinos at intermediate scales can have a significant impact on the inflationary predictions of these models. For one such model, values of the scalar spectral index lower than the tree level prediction of 0.968 are realized for plausible values of the seesaw parameters and a SM Higgs boson mass close to 130 GeV. A precise measurement of n_s by PLANCK, as well as measurement of the Higgs boson mass by LHC should provide stringent tests of this SM based inflationary scenario supplemented by type I seesaw physics.
118648696
Minimal supersymmetric hybrid inflation, flipped SU(5) and proton decay
Abstract Minimal supersymmetric hybrid inflation utilizes a canonical Kahler potential and a renormalizable superpotential which is uniquely determined by imposing a U(1) R -symmetry. In computing the scalar spectral index n s we take into account modifications of the tree level potential caused by radiative and supergravity corrections, as well as contributions from the soft supersymmetry breaking terms with a negative soft mass-squared term allowed for the inflaton. All of these contributions play a role in realizing n s values in the range 0.96–0.97 preferred by WMAP. The U(1) R -symmetry plays an important role in flipped SU ( 5 ) by eliminating the troublesome dimension five proton decay. The proton decays into e + π 0 via dimension six operators arising from the exchange of superheavy gauge bosons with a lifetime of order 10 34 – 10 36 years.
119219313
R-symmetry breaking in supersymmetric hybrid inflation
We consider a supersymmetric hybrid inflation scenario in which the U(1) $R$-symmetry is explicitly broken by Planck scale suppressed operators in the superpotential. We provide an example with minimal K\"ahler potential, with the $R$-symmetry breaking term relevant during inflation being $\alpha S^4$, where $S$ denotes the well-known gauge singlet inflaton superfield. The inflationary potential takes into account the radiative and supergravity corrections, as well as the soft supersymmetry breaking terms. For successful inflation, with the scalar spectral index in the currently preferred range, $n_s \approx 0.97 \pm 0.010$, $| \alpha |$ $\lesssim 10^{-7}$. The tensor to scalar ratio $r \lesssim 10^{-4}$, while $| \text{d} n_s / \text{d} \ln k | \sim \mathcal{O}(10^{-3})-\mathcal{O}(10^{-4})$
119236672
Red spectral tilt and observable gravity waves in shifted hybrid inflation
We consider supersymmetric shifted hybrid inflation models with a red tilted scalar spectral index n_s in agreement with the WMAP 7-yr central value. If non-minimal supergravity corrections are included, these models can also support a tensor-to-scalar ratio as large as r = 0.02, which may be observable by the Planck Satellite. In contrast to the standard supersymmetric hybrid inflation scenario, topological defects produced via gauge symmetry breaking are inflated away in the shifted version of the theory.
118474086
Higgs masses and electroweak precision observables in the lepton-flavor-violating MSSM
The work of S. H. was partially supported by CICYT (grant FPA 2010–22163-C02-01). S. H. and M. R. were supported by the Spanish MICINN’s Consolider-Ingenio 2010 Programme under grant MultiDark CSD2009-00064.