Multi-Messenger Theories of Gauge-Mediated Supersymmetry Breaking

We study gauge-mediated theories containing several messengers with the most general SU(5)-invariant mass and supersymmetry-breaking parameters. We show that these theories are predictive, containing only two relevant parameters more than the minimal gauge-mediated model. Hypercharge D-terms can contribute significantly to the right-handed charged sleptons and bring them closer in mass to the left-handed sleptons. The messenger masses must be invariant under either SU(5) or a ``messenger parity" to avoid spontaneous breaking of charge conservation.Comment: 13 pages, 2 figure

Towards a theory of quark and lepton masses

Has any progress been made on understanding and predicting the 13 parameters which describe the observed masses and mixing angles of the quarks and leptons? Arguments are given in favor of pursuing schemes in which grand unified and family symmetries provide many relations among these 13 parameters. A sequence of simple assumptions leads to a supersymmetric SO(10) theory with 8 predictions: $\tan \beta, m_t, V_{cb}, m_s, m_s/m_d$, $m_u/m_d, V_{ub}$ and the amount of CP violation $J$. These predictions are presented, together with experiments which will test them.Comment: (Talk given at Texas/Pascos Symposium), 18 page

Beyond the Standard Model

A few topics beyond the standard model are reviewed.Comment: 10 pages, ichep.st

Shaft Inflation

A new family of inflation models is introduced and studied. The models are characterised by a scalar potential which, far from the origin, approximates an inflationary plateau, while near the origin becomes monomial, as in chaotic inflation. The models are obtained in the context of global supersymmetry starting with a superpotential, which interpolates from a generalised monomial to an O'Raifearteagh form for small to large values of the inflaton field respectively. It is demonstrated that the observables obtained, such as the scalar spectral index and the tensor to scalar ratio, are in excellent agreement with the latest observations. Some discussion of initial conditions and eternal inflation is included.Comment: 7 pages, 3 figures. Published versio

Statistical Anisotropy and the Vector Curvaton Paradigm

The vector curvaton paradigm is reviewed. The mechanism allows a massive vector boson field to contribute to or even generate the curvature perturbation in the Universe. Contribution of vector bosons is likely to generate statistical anisotropy in the spectrum and bispectrum of the curvature perturbation, which will soon be probed observationally. Two specific models for the generation of superhorizon spectra for the components of an Abelian vector field are analysed. Emphasis is put on the observational signatures of the models when the vector fields play the role of vector curvatons. If future observations support the vector curvaton mechanism this will open a window into the gauge field content of theories beyond the standard model.Comment: LaTex, 26 pages, 1 figure, published versio

Supersymmetric Unification

The measured value of the weak mixing angle is, at present, the only precise experimental indication for physics beyond the Standard Model. It points in the direction of Unified Theories with Supersymmetric particles at accessible energies. We recall the ideas that led to the construction of these theories in 1981.Comment: 21 pages, latex, two figures available by snail-mail upon e-mail request; Talk presented at the International Conference on the History of Original Ideas and Basic Discoveries in Particle Physics held at Ettore Majorana Centre for Scientific Culture, Erice, Sicily, July 29-Aug.4, 199

Woodin for strong compactness cardinals

We give the definition of Woodin for strong compactness cardinals, the Woodinised version of strong compactness, and we prove an analogue of Magidor's identity crisis theorem for the first strongly compact cardinal.Comment: 20 pages, fixed proof of Theorem 4.1, minor corrections and addition

Soft Supersymmetry Breaking and the Supersymmetric Standard Model

We recall how the idea of Softly Broken Supersymmetry led to the construction of the Supersymmetric Standard Model in 1981. Its first prediction, the supersymmetric unification of gauge couplings, was conclusively verified by the LEP and SLC experiments 10 years later. Its other predictions include: the existence of superparticles at the electroweak scale; a stable lightest superparticle (LSP) with a mass of $\sim 100$ GeV, anticipated to be a neutral electroweak gaugino; the universality of scalar and gaugino masses at the unification scale. The original motivation for the model, solving the hierarchy problem, indicates that the superparticles should be discovered at the LHC or the TeVatron.Comment: Invited talk presented at the "Thirty Years of Supersymmetry" Symposium, University of Minnesota, October 13-15, 200

Dark Matter in Theories of Gauge-Mediated Supersymmetry Breaking

In gauge-mediated theories supersymmetry breaking originates in a strongly interacting sector and is communicated to the ordinary sparticles via SU(3)$\times$SU(2)$\times$U(1) carrying ``messenger'' particles. Stable baryons of the strongly interacting supersymmetry breaking sector naturally weigh $\sim$ 100 TeV and are viable cold dark matter candidates. They interact too weakly to be observed in dark matter detectors. The lightest messenger particle is a viable cold dark matter candidate under particular assumptions. It weighs less than 5 TeV, has zero spin and is easily observable in dark matter detectors.Comment: 10 pages, Late