Abstract
I present three related research projects in the broad area of general relativity. The first project involves a common question surrounding the concept of a time machine, i.e. whether or not such a machine can be physically realized using ordinary matter (non-exotic materials).Exotic materials are usually described as materials that violate the weak-energy condition, which captures the notion of positive mass-density. I present a physical model for a time machine that does not use any exotic materials of this type; however, my model appears to require the presence of naked singularities. The second project involves the development and numerical simulation of a physical model of an extended object (for eg. an astronaut or spaceship) approaching the weak singularity in the interior of a rapidly rotating black hole. My results suggest that safe passage through this singularity is quite possible, as argued by Ori nearly two decades ago. The last project is a new software tool based on Processing, Java and Python that allows one to visualize and manipulate space-time foliations.