Certain condensed matter systems exhibit fractionalization, whereby electrons appear to dissociate into multiple components. For instance, while electrons carry both spin and charge, the low-energy excitations in these systems can carry spin but no charge, charge but no spin, or even a fraction of the electrons’ initial charge. These fractional excitations do not arise from electrons breaking apart, but rather emerge from a highly nontrivial collective behavior driven by strong interactions. A natural setting to hunt for fractionalization is frustrated magnets — spin systems where local interactions cannot be simultaneously satisfied. Competing interactions can prevent magnetic ordering and give rise to disordered ground states characterized by long-range entanglement, known as quantum spin liquids (QSLs). A notable example of experimental interest is quantum spin ice (QSI), a three-dimensional QSL that realizes an analog of quantum electrodynamics, hosting emergent photon-like modes as well as gapped spinon excitations. In this talk, I will discuss efforts to theoretically model excitations in these systems. In particular, I will highlight how symmetry fractionalization can be used to make experimentally relevant predictions of static and dynamical signatures of fractionalization. I will then try to connect these predictions to dipolar-octupolar materials, for which there is mounting experimental evidence that they may realize QSI. This comparison suggests that cerium-based pyrochlore compounds are most compatible with the so-called π-flux QSI state, a symmetry-enriched QSL in which translation acts projectively on spinons. I will conclude by discussing how certain of these theoretical predictions also align with new polarized neutron scattering and ultra-low-temperature heat capacity experiments on a candidate material, which reveal features consistent with the presence of the long-sought-after emergent photons.