Related papers: Stringy Hidden Valleys
We study gaugino condensation in presence of an anomalous $U(1)$ gauge group and find that global supersymmetry is dynamically broken. An example of particular interest is provided by effective string models with 4-dimensional Green-Schwarz…
Four-dimensional strings with the standard model gauge group $SU(3)\times SU(2)\times U(1)$ give model-dependent predictions for the tree level weak mixing-angle. In the presence of an extra pseudo-anomalous gauged- ${U(1)}_X$, the value of…
``Anomalous'' U(1) gauge symmetry with Green-Schwarz anomaly cancellation mechanism is discussed in the orbifold construction of four-dimensional heterotic string models. Some conditions are given as criteria to have ``anomalous'' U(1) in…
We present a fermionic dark matter model mediated by the hidden gauge boson. We assume the QED-like hidden sector which consists of a Dirac fermion and U(1)$_X$ gauge symmetry, and introduce an additional scalar electroweak doublet field…
Embeddings of the standard model in type II string theory typically contain a variety of U(1) gauge factors arising from D-branes in the bulk. In general, there is no reason why only one of these - the one corresponding to weak hypercharge…
We study the general effects of anomalous U(1)_A gauge symmetry on soft supersymmetry (SUSY) breaking terms in large volume scenario, where the MSSM sector is localized on a small cycle whose volume is stabilized by the D-term potential of…
We show that supersymmetry can be broken mainly by hidden matter condensates in the observable matter direction in generic superstring models. This happens only when the fields whose VEVs give masses to hidden matter do not decouple at the…
We examine the possibility that dark matter may be the manifestation of dark forces of a hidden sector, i.e. "Dark Force = Dark Matter." As an illustrative and minimal example we consider the hidden SU(2)_h x U(1)_h gauge group. The hidden…
Supersymmetry breaking in a metastable vacuum allows one to build simple and concrete models of gauge mediation. Generation of gaugino masses requires that R-symmetry be broken in this vacuum. In general, there are two possible ways to…
A overview is given of the recent developments in the $U(1)_X$ Stueckelberg extensions of the Standard Model and of MSSM where all the Standard Model particles are neutral under the $U(1)_X$ but an axion which is absorbed is charged under…
We point out that pseudomoduli -- tree-level flat directions that often accompany dynamical supersymmetry breaking -- can be natural candidates for TeV-scale dark matter in models of gauge mediation. The idea is general and can be applied…
Several constructions motivate the existence of a dark $U(1)_D$ gauge boson which interacts with the Standard Model only through its kinetic mixing or loop induced processes. We describe two typical examples with specific signatures in…
In theories in which SUSY is broken on a brane separated from the MSSM matter fields, supersymmetry breaking is naturally mediated in a variety of ways. Absent other light fields in the theory, gravity will mediate supersymmetry breaking…
We provide, in a framework of vector-like gauge theories, concrete models for conformal sequestering of dynamical supersymmetry (SUSY) breaking in the hidden sector. If the sequestering is sufficiently strong, anomaly mediation of the SUSY…
We study the stability of supersymmetry breaking vacuum in the presence of cosmic strings arising in the messenger sector. For certain ranges of the couplings, the desired supersymmetry breaking vacua become unstable against decay into…
We consider a class of models with gauged U(1)_R symmetry in 4D N=1 supergravity that have, at the classical level, a metastable ground state, an infinitesimally small (tunable) positive cosmological constant and a TeV gravitino mass. We…
So far the most sophisticated experiments have shown no trace of new physics at the TeV scale. Consequently, new models with unexplored parameter regions are necessary to explain current results, re-examine the existing data, and propose…
As pointed out, chiral non-commutative theories exist, and examples can be constructed via string theory. Gauge anomalies require the matter content of individual gauge group factors, including U(1) factors, to be non-chiral. All ``bad''…
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…
We consider theories with one or more compact dimensions with size r > 1/M, where M is the fundamental Planck scale, with the visible and hidden sectors localized on spatially separated "3-branes." We show that a bulk U(1) gauge field…