Related papers: Constraints on Hidden Sector Gaugino Condensation

We study cosmic strings in the complex symmetron model, a scalar-tensor theory with a spontaneously broken local $U(1)$ symmetry in low matter density regions. Using numerical simulations, we show that these strings preferentially attach to…

An effective lagrangian analysis of gaugino condensation is performed in a supersymmetric gauge theory with field-dependent gauge couplings described with a linear multiplet. An original aspect of this effective lagrangian is the use of a…

We propose a fundamental theory whose low-energy effective theory provides a phenomenological description of electroweak baryogenesis, radiative neutrino mass generation, and dark matter. The model is based on SUSY SU(2)_H gauge theory with…

We discuss non-perturbative aspects of string effective field theories with N=1 supersymmetry in four dimensions. By the use of a scalar potential, which is on-shell invariant under the supersymmetric duality of the dilaton, we study…

Little experimental data bears on the question of whether there is a spontaneously broken hidden sector that has no Standard Model quantum numbers. Here we discuss the prospects of finding evidence for such a hidden sector through…

A fundamental task for the heterotic superstring theory is the determination of the effective action describing the physics of massless string excitations at low energies. This is necessary for the phenomenological applications of string…

In the Minimal Supersymmetric Standard Model, the higgsinos can have masses around the electroweak scale, while the other supersymmetric particles have TeV-scale masses. This happens in models of gauge-mediated SUSY breaking with a high…

The general SUSY soft breaking terms for a large class of phenomenologically relevant string scenarios (symmetric orbifolds) are given. They show a certain lack of universality, but not dangerous for flavor changing neutral currents. To get…

We consider supersymmetric compactifications of type IIB and the weakly coupled heterotic string with G resp.H-flux and gaugino condensation in a hidden sector included. We point out that proper inclusion of the non-perturbative effects…

Recently, we demonstrated the existence of heterotic--string solutions in which the observable sector effective field theory just below the string scale reduces to that of the MSSM, with the standard observable gauge group being just…

Hidden sector glueball dark matter is well motivated by string theory, compactifications of which often have extra gauge groups uncoupled to the visible sector. We study the dynamics of glueballs in theories with a period of late time…

The lack of evidence for new physics beyond the standard model at the LHC points to a paucity of new particles near the weak scale. This suggests that the weak scale is tuned and that supersymmetry, if present at all, is realized at higher…

Natural supersymmetry with light higgsinos is most likely to emerge from the string landscape since the volume of scan parameter space shrinks to tiny volumes for electroweak unnatural models. Rather general arguments favor a landscape…

Based on the analogy with superconductor physics we consider a scalar-vector-tensor gravitational model, in which the dark energy action is described by a gauge invariant electromagnetic type functional. By assuming that the ground state of…

We develop some techniques which allow an analytic evaluation of space-like observables in high temperature lattice gauge theories. We show that such variables are described extremely well by dimensional reduction. In particular, by using…

We point out that type I string theory in the presence of internal magnetic fields provides a concrete realization of split supersymmetry. To lowest order, gauginos are massless while squarks and sleptons are superheavy. We build such…

We investigate the possibility of large CP- violating phases in the soft breaking terms derived in superstring models. The bounds on the electric dipole moments (EDM's) of the electron and neutron are satisfied through cancellations…

I discuss some current thoughts on how low-energy measurements and consistency constrain theories at high energies with emphasis on string theory. I also discuss some recent work on the dynamics of supersymmetric gauge theories.

In Gravity Unified Theories all operators that are consistent with the local gauge and discrete symmetries are expected to arise in the effective low-energy theory. Given the absence of multiplets like 126 of SO(10) in string models, and…

Several models of dark matter motivate the concept of hidden sectors consisting of SU(3)_C x SU(2)_L x U(1)_Y singlet fields. The interaction between our and hidden matter could be transmitted by new abelian U'(1) gauge bosons A' mixing…