Although this dissertation has several themes, the central question being asked is, what insights can we gain into quantum gravity without fully quantizing gravity, and whether any experiments can be done to probe the interface between quantum me- chanics and general relativity. During the process of asking this question we explored quantum optics, optomechanics, gravitational waves, and black holes. We found that the dynamical Casimir effect in our superconducting radio frequency cavities will have a threshold too high for the observation of squeezed vacuum. This is true whether we assume the vacuum is composed of gravitons or photons. We found that gravita- tional waves do interact with quantum macroscopic states differently than for normal matter, but this does not at present lead to any observable effect. We found that in general, the unphysical anomalies in classical spacetimes are removed when quantum mechanics is applied. We showed that Cauchy horizons which lead to mass inflation, and naked singularities which lead to issues with causality, are removed if the prob- lems are treated correctly. By correctly, we mean applying quantum mechanics when it is non negligible, and applying the quantum mechanical idea of intrinsic mass to gravitating matter.