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.
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.
118371448
Non-Minimal B-L Inflation with Observable Gravity Waves
Abstract We consider non-minimal λ ϕ 4 inflation in a gauged non-supersymmetric U ( 1 ) B − L model containing the gravitational coupling ξ R Φ † Φ , where R denotes the Ricci scalar and the standard model singlet inflaton field Φ spontaneously breaks the U ( 1 ) B − L symmetry. Including radiative corrections, the predictions 0.956 ≲ n s ≲ 0.984 and 0.007 ≲ r ≲ 0.1 for the scalar spectral index and tensor to scalar ratio r lie within the current WMAP 1- σ bounds. If the B − L symmetry breaking scale is of order a TeV or so, one of the three right handed neutrinos is a plausible cold dark matter candidate. Bounds on the dimensionless parameters λ , ξ and the gauge coupling g B − L are obtained.
118703701
Inflation in supersymmetric SU(5)
We analyze the adjoint field inflation in supersymmetric (SUSY) SU(5) model. In minimal SUSY SU(5) hybrid inflation monopoles are produced at the end of inflation. We therefore explore the nonminimal model of inflation based on SUSY SU(5), like shifted hybrid inflation, which provides a natural solution for the monopole problem. We find that the supergravity corrections with nonminimal Kaehler potential are crucial to realize the central value of the scalar spectral index n{sub s{approx_equal}}0.96 consistent with the 7 yr WMAP data. The tensor to scalar ratio r is quite small, taking on values r < or approx. 10{sup -5}. Because of R symmetry massless SU(3) octet and SU(2) triplet supermultiplets are present and could spoil gauge coupling unification. To keep gauge coupling unification intact, light vectorlike particles are added which are expected to be observed at LHC.
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.
119269294
Simplified smooth inflation with observable gravity waves
We consider a simplified version of supersymmetric smooth hybrid inflation which contains a single ultraviolet cutoff ${m}_{P}=2.4\ifmmode\times\else\texttimes\fi{}{10}^{18}\text{ }\text{ }\mathrm{GeV}$, instead of the two cutoffs ${m}_{P}$ and ${M}_{*}\ensuremath{\sim}\mathrm{\text{few}}\ifmmode\times\else\texttimes\fi{}{10}^{17}\text{ }\text{ }\mathrm{GeV}$ that are normally employed. With global supersymmetry the scalar spectral index ${n}_{s}\ensuremath{\simeq}0.97$, which is in very good agreement with the WMAP observations. With a nonminimal K\"ahler potential, the supergravity version of the model is compatible with the current central values of ${n}_{s}$ and also yields potentially observable gravity waves (tensor to scalar ratio $r\ensuremath{\lesssim}0.02$).
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.