Non-Minimal and Non-Universal Supersymmetry

I motivate and discuss non-minimal and non-universal models of supersymmetry and supergravity consistent with string unification at $10^{16}$ GeV.Comment: 10 pages, Latex. Plenary talk given at 6th Workshop in High Energy Physics Phenomenology (WHEPP 6), Chennai (Madras), India, 3-15 Jan 200

Cosmological constant in SUGRA models and the multiple point principle

The tiny order of magnitude of the cosmological constant is sought to be explained in a model involving the following ingredients: supersymmetry breaking in N=1 supergravity and the multiple point principle. We demonstrate the viability of this scenario in the minimal SUGRA model.Comment: 18 pages, 2 figures, Talk given at Nuclear Physics Department of the Russian Academy of Sciences (RAS) Conference on Physics of Fundamental Interactions, Moscow, Russia, 2-6 Dec 2002; to appear in Phys.Atom.Nuc

Small SUSY phases in string-inspired supergravity

In supersymmetric models, there are new CP violating phases which, if unsuppressed, would give a too large neutron electric dipole moment. We examine the possibility of small SUSY phases in string-inspired supergravity models in which supersymmetry is broken by the auxiliary components of the dilaton and moduli superfields. It is found that the SUSY phases can be suppressed by a small factor governing the breakdown of the approximate Peccei Quinn symmetries nonlinearly realized for the moduli superfields that participate in supersymmetry breaking. In many cases, the symmetry breaking factors are exponentially small for moderately large values of the moduli, leading to small phase values in a natural way.Comment: 15pages, Latex, SNUTP 93-8

A Note On R-Parity Violation and Fermion Masses

We consider a class of supersymmetric SU(3)\times SU(2)\times U(1) multihiggs models in which R-parity is violated through bilinear Higgs-lepton interactions. The required, due to R-parity violation, higgs-lepton rotations introduce an alternative way to generate the phenomenologically desirable fermion mass matrix structures independently of the equality of Yukawas, possibly imposed by superstring or other unification.Comment: 8 pages, uses LaTeX2

Some Implications of a Supersymmetric Model with R-Parity Breaking Bilinear Interactions

We investigate a supersymmetric scenario where R-parity is explicitly broken through a term bilinear in the lepton and Higgs superfields in the superpotential. We show that keeping such a term alone can lead to trilinear interactions, similar to those that are parametrized by $\lambda$-and ${\lambda}'$ in the literature, involving the physical fields. The upper limits of such interactions are predictable from the constraints on the parameter space imposed by the lepton masses and the neutrino mass limits. It is observed that thus the resulting trilinear interactions are restricted to values that are smaller than the existing bounds on most of the $\lambda$-and ${\lambda}'$-parameters. Some phenomenological consequences of such a scenario are discussed.Comment: 26 Pages, 6 Postscript figures, Latex. An additional set of references has been included. Typographic corrections have been made. Figures remain all unchanged. An additional typographic correction has been mad

Physics Beyond the Standard Model and Cosmological Connections: A Summary from LCWS 06

The International Linear Collider (ILC) is likely to provide us important insights into the sector of physics that may supersede our current paradigm viz., the Standard Model. In anticipation of the possibility that the ILC may come up in the middle of the next decade, several groups are vigourously investigating its potential to explore this new sector of physics. The Linear Collider Workshop in Bangalore (LCWS06) had several presentations of such studies which looked at supersymmetry, extra dimensions and other exotic possibilities which the ILC may help us discover or understand. Some papers also looked at the understanding of cosmology that may emerge from studies at the ILC. This paper summarises these presentations.Comment: 8 pages (including cover page) LaTeX, Summary talk presented at the International Linear Collider Workshop in Bangalore, India in March 200