Abstract
Alternatives to General Relativity (GR) are often superficially similar to GR itself, leading some physicists to take for granted that their shared structure has the same interpretation in all cases. However, following Brown (2005), several philosophers have argued that such superficial similarities between GR and modified theories of gravity do not necessarily indicate a commitment to shared background structures. This symposium proposes to investigate how such differences in interpretation arise in the case of various theories of modified gravity. To do so, we focus on identifying and interpreting the ontological commitments of theories of modified gravity. Some of the questions considered include: How are matter and geometry represented in each theory? (How) can theories of modified gravity be distinguished from theories with dark matter and/or dark energy? In addition to considering theories in isolation to understand their ontological commitments, we will also consider how similar terms operate across different theories of gravity and any relations that may exist between theories.