10 research outputs found
LHC String Phenomenology
We argue that it is possible to address the deeper LHC Inverse Problem, to
gain insight into the underlying theory from LHC signatures of new physics. We
propose a technique which may allow us to distinguish among, and favor or
disfavor, various classes of underlying theoretical constructions using
(assumed) new physics signals at the LHC. We think that this can be done with
limited data , and improved with more data. This is because of
two reasons -- a) it is possible in many cases to reliably go from
(semi)realistic microscopic string construction to the space of experimental
observables, say, LHC signatures. b) The patterns of signatures at the LHC are
sensitive to the structure of the underlying theoretical constructions. We
illustrate our approach by analyzing two promising classes of string
compactifications along with six other string-motivated constructions. Even
though these constructions are not complete, they illustrate the point we want
to emphasize. We think that using this technique effectively over time can
eventually help us to meaningfully connect experimental data to microscopic
theory.Comment: 50 Pages, 13 Figures, 3 Tables, v2: minor changes, references adde
Intersecting Brane Worlds -- A Path to the Standard Model ?
In this review we describe the general geometrical framework of brane world
constructions in orientifolds of type IIA string theory with D6-branes wrapping
3-cycles in a Calabi-Yau 3-fold. These branes generically intersect in points
on the internal space, and the patterns of intersections govern the chiral
fermion spectra. We discuss how the open string spectra in intersecting brane
models are constructed, how the Standard Model can be embedded, and also how
supersymmetry can be realized in this class of string vacua. After the general
considerations we specialize the discussion to the case of orbifold backgrounds
with intersecting D6-branes and to the quintic Calabi-Yau manifold. Then, we
discuss parts of the effective action of intersecting brane world models.
Specifically we compute from the Born-Infeld action of the wrapped D-branes the
tree-level, D-term scalar potential, which is important for the stability of
the considered backgrounds as well as for questions related to supersymmetry
breaking. Second, we review the recent computation concerning of gauge coupling
unification and also of one-loop gauge threshold corrections in intersecting
brane world models. Finally we also discuss some aspects of proton decay in
intersecting brane world models.Comment: 31 pages, To appear in the proceedings of the RTN-workshop ``The
quantum structure of spacetime and the geometric nature of fundamental
interactions'', September 2003 in Copenhagen, revised version contains new
refs and one corrected equatio
On N=1 gauge models from geometric engineering in M-theory
We study geometric engineering of four-dimensional N=1 gauge models from M-theory on a seven-dimensional manifold with G_2 holonomy. The manifold is constructed as a K3 fibration over a three-dimensional base space with ADE geometry. The resulting gauge theory is discussed in the realm of (p,q) webs. We discuss how the anomaly cancellation condition translates into a condition on the associated affine ADE Lie algebras