General and subject specific (physics) GRE tests will not be required for graduate student applications for the 2020/21 academic year. This decision was made in light of the ongoing COVID-19 pandemic, and the associated difficulties taking these test, in particular for international applicants.
The department will also review possible permanent changes to the GRE requirements. Recently, the value of the subject GRE test has been called into questions, and many programs have dropped the requirement altogether (see for example the recent article in Physics Today).
You can find more information on the physics graduate program at Notre Dame by clicking here.