ArXiv paper: http://arxiv.org/abs/1210.1847 This work attempts to draw out the presence of a simulation by looking for tiny violations of known/expected symmetries, which is always worth doing. We should note, however, that an excellent simulation could exactly cover its tracks, lest the underlying architecture cause unintended artifacts. From a CS perspective, the simulation's developer might create unit tests that…
"With finite resources at their disposal, our descendants will likely make use of effective theory methods, as is done today, to simulate every-increasing complexity, by, for instance, using meshes that adapt to the relevant physical length scales, or by using fluid dynamics to determine the behavior of fluids, which are constrained to rigorously reproduce the fundamental laws of nature."
It's possible that if we were simulated, the simulators aren't actually trying to hide the nature of our universe from us. It's also possible even though the simulation started with a 'simple' framework that they could have hidden better if desired, that by becoming a self aware information system we can no longer be switched off / restarted without violating their ethical constraints. So it's possible that the limits a simulation actually are detectable.
Of course as someone said, if the simulators were actively monitoring your thoughts with the intent of stopping you from finding the boundaries then there truly would be nothing you could do.