Kaplan, David BSun, Sichun2014-10-202014-10-202014-10-202014Sun_washington_0250E_13072.pdfhttp://hdl.handle.net/1773/26924Thesis (Ph.D.)--University of Washington, 2014In this thesis, I focus on a few different applications of modern quantum field theory. I start with a model beyond the standard model: Little Flavor Theory and its related collider phenomenology. This model combines a flavor theory with Little Higgs theory, to explain the origin of flavor and little hierarchy problem at the same scale. The field theory on intersecting D-brane has a monopole. The theta vacuum interface could support an electron-monopole dyon system. A certain configuration of D-branes is dual to Wilson lines on the field theory side. These are the other special topics in this thesis. I also include a chapter on a finite temperature field theory method to calculate the corrections to the equation of state.application/pdfen-USCopyright is held by the individual authors.D-brane; field theory; finite temperature; flavor; Higgs; monopolePhysicsphysicsThesis