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Motivated by the coincidence between the Hubble scale during inflation and the typical seesaw neutrino mass scale, we present a supergravity model in which the inflaton is identified with a linear combination of right-handed sneutrino fields. The model accommodates an inflaton potential that is flatter than quadratic chaotic inflation, resulting in a tensor-to-scalar ratio that is measurable but not yet ruled out. Small CP violation in the neutrino mass matrix and supersymmetry breaking yield an evolution in the complex plane for the sneutrino fields. This induces a net lepton charge that, via the Affleck-Dine mechanism, can be the origin of the observed baryon asymmetry of the Universe. [ABSTRACT FROM AUTHOR]

We discuss the proton lifetime in pure gravity mediation models with nonuniversal Higgs soft masses. Pure gravity mediation olfers a simple framework for studying SU(5) grand unified theories with a split supersymmetrylike spectra. We find that for much of the parameter space gauge coupling unification is quite good leading to rather long lifetimes for the proton. However, for m3/2 ~ 60 TeV and tan β ~ 4, for which gauge coupling unification is also good, the proton lifetime is short enough that it could be in reach of future experiments. [ABSTRACT FROM AUTHOR]

Pure gravity mediation, with two free parameters, is a minimalistic approach to supergravity models, yet it is capable of incorporating radiative electroweak symmetry breaking, a Higgs mass in agreement with the experimental measurement, without violating any phenomenological constraints. The model may also contain a viable dark matter candidate in the form of a wino. Here, we extend the minimal model by allowing the g term to be a free parameter equivalent to allowing the two Higgs soft masses, m1 and m2, to differ from other scalar masses, which are set by the gravitino mass. In particular, we examine the region of parameter space where μ « m3/2, in which case the Higgsino becomes the lightest supersymmetric particle and a dark matter candidate. We also consider a generalization of pure gravity mediation that incorporates a Peccei-Quinn symmetry which determines the g term dynamically. In this case we show that the dark matter may either be in the form of an axion and/or a neutralino and that the lightest supersymmetric particle may be either a wino, bino, or Higgsino. [ABSTRACT FROM AUTHOR]

We consider models of pure gravity mediation in which scalar mass universality is imposed at the grand unified scale and gaugino masses are generated through loops. The minimal model requires a very restricted range for tanβ ≈ 2-3 and scalar masses (set by the gravitino mass) of order 300 TeV-1.5 PeV in order to obtain a Higgs mass near 126 GeV. Here we augment the minimal model with one or more sets of vector multiplets (either a 10 and 10 pair or one or more 5 and 5 pairs). If coupled to the minimal supersymmetric standard model Higgs, these allow for radiative electroweak symmetry breaking over a significantly larger range of tanβ ≈2-40 and can fit the Higgs mass with much smaller values of the gravitino mass. In these models, the lightest supersymmetric particle is often the bino, and in order to satisfy the relic density constraint, the bino must be nearly degenerate with either the wino or gluino. In the models considered here, bino gluino coannihilations determine the relic density and since the two are nearly degenerate, LHC limits on the gluino mass are greatly relaxed allowing light relatively gravitinos and gluino masses well within the reach of the LHC. [ABSTRACT FROM AUTHOR]

Here we give a broad overview of the more natural spectra allowed by the LHC when UDD R-parity violation is allowed. Because R-parity violation removes the missing energy signals in colliders, the experimental constraints on the gluino, stops, sbottoms, and Higgsinos are relatively mild. We also show that UDD R-parity violation and lepton number conservation can be made consistent with grand unification. This feat is achieved through the product unification, SU(5) X U(3). In this model, mixing of the standard model quarks with additional quarklike particles charged under the U(3) generate a UDD R-parity violating operator. Furthermore, these models are also capable of generating a "natural" spectra. The emergence of these more natural low-scale spectra relies heavily on the fact that the gaugino masses are nonuniversal, a natural consequence of product unification. [ABSTRACT FROM AUTHOR]

We propose a new model for producing a Higgs boson mass near 125 GeV within the MSSM. By coupling the MSSM Higgs boson to a set of strongly interacting fields, large corrections to the Higgs quartic coupling are induced. Although the Higgs doublets do not participate in the strong dynamics, they feel the effects of the strongly coupled sector via (semi)perturbative interactions. These same strong dynamics are also capable of generating the &mgr; term. Additionally, this strong sector is in the conformai window, which drives the couplings to an infrared fixed point and naturally generates model parameters of the appropriate size. [ABSTRACT FROM AUTHOR]

Recently, the ATLAS and CMS collaborations reported exciting hints of the standard model-like Higgs boson with a mass around 125 GeV. A Higgs boson this heavy is difficult to realize in conventional models of gauge mediation. Here we revisit the lightest Higgs boson mass in "more generic gauge mediation," where the Higgs doublets mix with the messenger doublets. We show that a Higgs boson mass around 125 GeV can be realized in more generic gauge mediation models, even for a relatively light gluino mass, mgluino ∼ 1 TeV. We also show that the muon anomalous magnetic moment can be within 1&sgr; of the experimental value for these models, even when the Higgs boson is relatively heavy. We also discuss the LHC constraints and the prospects of discovery. [ABSTRACT FROM AUTHOR]

We present a supersymmetric solution to the strong CP problem based on spontaneous CP violation which simultaneously addresses the effects coming from supersymmetry breaking. The generated CP violating phase is communicated to the quark sector by interacting with a heavy quark a la Nelson-Barr. The Majorana mass of the right handed neutrinos is generated by interactions with the CP violating sector and so does not conserve CP. This gives the neutrino sector a nontrivial CP violating phase which can then generate the baryon asymmetry of the universe through leptogeneis. The problematic phase in the supersymmetry breaking parameters are suppressed by appealing to a particular gauge mediation model which naturally suppresses the phases of the tree-level gluino mass and Higgs bilinear masses. This suppression plus the fact that in gauge mediation all loop generated flavor and CP violation is of the minimal flavor violation variety allows for a complete and consistent solution to the strong CP problem. [ABSTRACT FROM AUTHOR]

Product group unification is an attractive alternative to simple grand unification. It solves the infamous doublet-triplet splitting problem and the dimension-5 proton decay problems without introducing any fine-tuning. Furthermore, the matter multiplets are still embedded into unified SU(5) representations. In this paper, we discuss proton decay for the simplest product group unification model based on SU(5)×U(2)H. We find that the minimal setup of the model has already been excluded by dimension-6 proton decay. We also show that a simple extension of the model, with naturally generated SU(5) incomplete multiplets, can rectify this problem. We find that the proton lifetime will be in reach of coming experiments like DUNE and Hyper-K, when the mass of the incomplete multiplet is associated with the Peccei-Quinn-symmetry breaking. In this case, the dark matter may be an admixture of the Wino lightest supersymmetric particle and the axion. [ABSTRACT FROM AUTHOR]

We revisit the minimal supersymmetric SU(5) grand unified theory with three right-handed neutrinos in which universality conditions for soft-supersymmetry breaking parameters are imposed at an input scale above the unification scale. If the Majorana masses for the neutrinos are around 1015 GeV, large mixing angles and phases in the neutrino sector lead to flavor violation and CP violation in the right-handed down-squark and left-handed slepton sectors. Since the observed Higgs boson mass and the proton decay constraints indicate that sfermions have masses larger than a few TeV, flavor and CP constraints are less restrictive. We explore the constraints on models with universal soft-supersymmetry breaking input parameters coming from proton stability, electric dipole moments, μ→eγ decays, and the Higgs mass observed at the LHC. Regions compatible with all constraints can be found if nonzero A-terms are taken. [ABSTRACT FROM AUTHOR]

We present a dynamical cosmological solution that simultaneously accounts for the early inflationary stage of the Universe and solves the supersymmetric little hierarchy problem via the relaxion mechanism. First, we consider an inflationary potential arising from the D term of a newU(1) gauge symmetry with a Fayet-Iliopolous term that is independent of the relaxion. A technically natural, small U (1) gauge coupling, g ≤10-8, allows for a low Hubble scale of inflation, HI ≤105GeV, which is shown to be consistent with Planck data. This feature is then used to realize a supersymmetric two-field relaxion mechanism, where the second field is identified as the inflaton provided that HI ≤ 10GeV. The inflaton controls the relaxion barrier height allowing the relaxion to evolve in the early Universe and scan the supersymmetric soft masses. After electroweak symmetry is broken, the relaxion settles at a local supersymmetry-breaking minimum with a range of F -term values that can naturally explain supersymmetric soft mass scales up to 106GeV. [ABSTRACT FROM AUTHOR]