| dc.description.abstract | Supersymmetry is an important concept in modern high energy physics. It has found many applications
in theoretical considerations of supersymmetric gauge theories as well as in phenomenological
approaches to physics beyond the Standard Model. In this report we discuss some recent progress
in supersymmetric eld theories in four and six dimensions.
After introducing basic ideas and properties of supersymmetry we review the concept of scattering
amplitudes in maximally supersymmetric theories in four dimensions before constructing a
related framework in six dimensions. Here, the spinor helicity formalism and on-shell superspace
were recently developed for six-dimensional gauge theories with (1,1) supersymmetry. We combine
these two techniques with (generalised) unitarity, which is a powerful technique to calculate scattering
amplitudes in any massless theory. As an application we calculate one-loop superamplitudes
with four and ve external particles in the (1,1) theory and perform several consistency checks on
our results.
Within the area of phenomenological applications of supersymmetric gauge theories, we brie
y
review basic properties of supersymmetry breaking and gauge mediation in four dimensions. An
important recent development has been the concept of theories with broken supersymmetry and
metastable vacua. By using the advances of Seiberg duality, we examine a metastable N = 1
Macroscopic SO(N) SQCD model of Intriligator, Seiberg and Shih (ISS). We introduce various
baryon and meson deformations, including multitrace operators. In this setup, direct fundamental
messengers and the symmetric pseudomodulus messenger mediate supersymmetry breaking to a
minimal supersymmetric Standard Model. We compute gaugino and sfermion masses and compare
them for each deformation type. We also explore reducing the rank of the magnetic | en_US |
