Tests of Lorentz and CPT Invariance in Space

I give a brief overview of recent work concerning possible signals of Lorentz violation in sensitive clock-based experiments in space. The systems under consideration include atomic clocks and electromagnetic resonators of the type planned for flight on the International Space Station.Comment: 11 pages, presented at the 2003 NASA/JPL Workshop for Fundamental Physics in Space, Oxnard, California, April 200

Higher-order Lorentz violations in electrodynamics

The Standard-Model Extension (SME) provides a theoretical framework for tests of Lorentz invariance. To date, most studies have focused on the minimal SME, which restricts attention to operators of renormalizable dimension. Here, we review recent studies involving the nonrenormalizable photon sector of the SME.Comment: Presented at the Fifth Meeting on CPT and Lorentz Symmetry, Bloomington, Indiana, June 28-July 2, 201