Abstract:
In this dissertation, the renormalization group equations in five dimensional minimal super symmetric standard model plus additional fields were derived. the gauge couplings constants was studied, the evolution was founded does not follow a logarithmic running, but follow power law running, this is because of the presence of KK states which at contributes at energy greater than the compactification scale Q=1/R . The coupling constant were noticed unified at energyQ=〖10〗^5.6 GeV, which is lowered in comparison with the unification scale in the 4D MSSM. the tri-linear soft breaking terms,A_(t,b,τ) was vanish at the unification scale and generating large A_t at electroweak scale through the renormalization group equation. However this large value of A_t is driven by the gluino mass. We have shown that, in five dimensional models that one can accommodate the correct Higgs mass and producing light stop quark mass below 2 TeV.
