Topological responses such as the integer quantum Hall effect provide a concrete manifestation of topology in electronic systems. Beyond electromagnetic response phenomena, electrons can also respond to deformations of the underlying crystal lattice. In this talk, I will discuss the structure of effective actions describing the combined crystalline-electromagnetic response of semimetals. I will motivate this by first considering the well-studied electromagnetic response of strong topological insulators, then coupling these systems to a gauge field that captures the underlying crystalline symmetry. I will then present a lattice model which realizes two of the response actions to demonstrate their validity. Lastly, I will discuss a subtlety of the crystalline response which points toward future work.
