In this thesis a new method for solving the UV/IR mixing problem in noncommutative field theories. We apply this method in the scalar and gauge theories. Theories on a fuzzy torus is also investigated. The stabilization of this fuzzy torus is studied. The noisy behavior of the torus due to quantum gravitational effects is studied. Finally we investigate the trans Planckian effects on the cosmic microwave background power spectrum. We show that these effects leads to a new theory which give a better result.
