Overview This paper is written as background for a proposed Grand Challenge in Computing Research, entitled Science for Global Ubiquitous Computing. The paper has a specific purpose: to trace the evolution of theoretical models for distributed and mobile computing, and the mutual influence between these models on the one hand and software design and development on the other. It also discusses m...

Recent measurements of the values of gauge coupling constants as well as neutrino properties support the idea of a grand unified (GUT) description of particle physics at a large scale of MGUT ∼ 10 16 GeV. We discuss a strategy to incorporate this picture in the framework of superstring theory. In such a scheme successful predictions of GUTs can be realized while some of the more problematic asp...

We consider a new class of light vectorlike exotics with fractional electric charge which do not come in complete representations of a grand unified gauge group, and are nevertheless compatible with gauge coupling unification and other predictions from Grand Unified Theories. Such states naturally arise in orbifold constructions of the heterotic string. Some aspects of their phenomenology and t...

The study for lepton flavor violation combined with the neutrino oscillation may provide more information about the lepton flavor structure of the grand unified theory. In this paper, we study two lepton flavor violation processes , τ → μγ and Z → τμ, in the context of supersymmetric SO(10) grand unified models. We find the two processes are both of phenomenological interest. In particular the ...

If you take a drive through the old town of Karachi at some point may pass Frere Hall. Once centrepiece colonial town, this grand building now serves as library, exhibition space, ...

Corporate governance (CG) is an important effort to ensure accountability and responsibility and is a set of principles, which should be incorporated into every part of the organization. This study focused on the state of Corporate Governance (CG) in two categories of the banking industries: Conventional Banks and Islamic Banks. As Conventional Banks and Islamic Banks differ a great deal in the...

The problem of fermion masses and mixings is discussed in the context of super-symmetric grand unification theories. Some predictive frameworks based on the SU(5), SO(10) and SU(6) models are reviewed.

A review of baryon and lepton conservation in supersymmetric grand unified theories is given. Proton stability is discussed in the minimal SU(5) supergravity grand unification and in several non-minimal extensions such as the SU(3), SO(10) and some string based models. Effects of dark matter on proton stability are also discussed and it is shown that the combined constraints of dark matter and ...