Related papers: String no-scale supergravity
We study a class of type I string models with supersymmetry broken on the world-volume of some D-branes and vanishing tree-level potential. Despite the non-supersymmetric spectrum, supersymmetry is non-linearly realized on these D-branes,…
Recently, a potential for string backgrounds is obtained from string geometry theory, which is a candidate for the non-perturbative formulation of string theory. By substituting a string phenomenological model with free parameters to the…
We study the cosmology of a string derived supersymmetric flipped $SU(5)$ model in the context of free-fermionic heterotic constructions that allow full calculability of the effective supergravity in perturbation theory around the fermionic…
I discuss the construction of realistic superstring standard--like models in the four dimensional free fermionic formulation. I discuss the massless spectrum of the superstring standard--like models and the texture of fermion mass matrices.…
We study the magnitudes of soft SUSY breaking parameters in heterotic string models with anomalous U(1) symmetry. In most cases, D-term contribution to soft scalar masses is expected to be comparable to or dominant over other contributions…
In the context of phenomenological models in which the soft supersymmetry-breaking parameters of the MSSM become universal at some unification scale, M_{in}, above the GUT scale, \mgut, it is possible that all the scalar mass parameters…
The particle spectrum of the supersymmetric extension of the standard model with a gauge singlet is studied. Soft supersymmetry breaking terms are explicitly chosen to be non-universal according to orbifold string theory. they depend on…
We show that if there is a realistic 4-d string, the dilaton and moduli supermultiplets will generically acquire a small mass O(m_{3/2}), providing the only vacuum-independent evidence of low-energy physics in string theory beyond the…
In the generalized minimal supergravity (GmSUGRA) scenario, we systematically study the supersymmetry breaking scalar masses, Standard Model fermion Yukawa coupling terms, and trilinear soft terms in SU(5) models with the Higgs fields in…
We review symmetries protecting a zero value for the cosmological constant in no--scale supergravity and reveal the connection between the Multiple Point Principle, no--scale and superstring inspired models.
A review of the soft supersymmetry-breaking parameters and the $\mu$ term arising in superstring models is performed paying special attention to their phenomenological implications. In particular, the violation of the scalar mass…
We systematically investigate the finite set of possible gauge groups and matter content for N = 1 supergravity theories in six dimensions with no tensor multiplets, focusing on nonabelian gauge groups which are a product of SU(N) factors.…
I survey the parameter space of NAHE-based free fermionic heterotic string models. First, I discuss flat directions of the low energy effective field theories and show that D-flat directions need not be isomorphic to gauge invariant…
We discuss phenomenological aspects of no-scale supergravity inflationary models motivated by compactified string models, in which the inflaton may be identified either as a K\"ahler modulus or an untwisted matter field, focusing on models…
We propose a simple gauge-mediated supersymmetry breaking model in which suitable soft breaking masses are dynamically generated without relying on a messenger sector. This model is constructed as an extention of the 3-2 model and needs no…
We present a numerical study of the spectrum of an asymptotically non-free $SU(2)$ gauge theory with $N_f=24$ massive fermion flavors. For such large number of flavors, asymptotic freedom is lost and the massless theory is governed by a…
In quasi-realistic string models that contain an anomalous U(1) the non-zero Fayet-Iliopoulos term triggers the shifting of the original vacuum to a new one along some flat direction, so that SUSY is preserved but the gauge group is…
In these lectures I review the progress made over the last few years in the subject of string and string-inspired phenomenology. I take a practical approach, thereby concentrating more on explicit examples rather than on formal…
We construct an explicit 5-dimensional supergravity model that realizes the "no scale" mechanism for supersymmetry breaking with no unstable moduli. Supersymmetry is broken by a constant superpotential localized on a brane, and the radion…
We survey a variety of proposals for new physics at high scales that serve to relate the multitude of soft supersymmetry breaking parameters of the MSSM. We focus on models where the new physics results in non-universal soft parameters, in…