Caspar Jacobs: What is the Significance of Direct Empirical Significance?
There is a substantial debate in the literature over whether local symmetries have what is called ‘Direct Empirical Significance’ (DES). Healey (2009), Kosso (2000) and Brading and Brown (2004) argue against, but more recently Greaves and Wallace (2014), Teh (2015) and Gomes (2019) have argued that local symmetries do have DES.
However, these philosophers have not made clear the importance of this question: what is the significance of direct empirical significance? I will argue that the significance of DES is very limited. There are two important questions regarding the interpretation of symmetries: first, are symmetry-related models physically equivalent?; and second, in which cases should we look for a reduced theory without certain symmetries? I believe that DES has no impact on either of these questions.