There are different ideas about how to quantize gravity that are currently pursued. In each approach trade-offs are made between different concepts that are clearly defined in quantum theory or general relativity but that can not be combined. One such fundamental concept is the Lorentzian structure of space-time.

In this defense I will present my research on Causal Dynamical Triangulations and Causal Set Theory, and the consequences that their focus on Lorentzian structure engenders.