MG11 
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Properties of gravitational waves in Cosmological General Relativity

The 5D Cosmological General Relativity theory developed by Carmeli reproduces all of the results that have been successfully tested for Einstein's 4D theory. However the Carmeli theory because of its fifth dimension, the velocity of the expanding universe, predicts something different for the propagation of gravity waves on cosmological distance scales. This analysis indicates that gravitational radiation may not propagate as an unattenuated wave where effects of the Hubble expansion are felt. In such cases the energy does not travel over such large length scales but is evanescent and dissipated into the surrounding space as heat.

Precision microwave measurements to test Lorentz Invariance

We present recent and new experiments to test Local Lorentz Invariance (LLI) at the University of Western Australia. This includes the latest results of a continuously rotating cryogenic microwave oscillator. Initial results from this experiment improved limits set by previous non-rotating experiments by more than a factor of 7 with only 3 months of data. Now, with over 12 months of data, we have reduced the noise floor by a factor of 2. Also, we present a new experiment that is sensitive to the scalar and parity-odd coefficients for Lorentz violation in the photon sector of the Standard Model Extension (SME) of particle physics. To do this, we are developing a high precision microwave interferometer with different electromagnetic properties in the two arms. With present technology we estimate that the scalar and parity odd coefficients may be measured at sensitivity better than parts in 10^11 and 10^15 respectively, which represents six orders of magnitude improvement in the former and four orders for the latter.