I've found a few similar questions here, but I'm still not sure in this specific case if there should be a preference for using the word arise or arises:
Originally proposed before BCS theory as a phenomenological (i.e. non-microscopic) description of type-I superconductors, Ginzburg–Landau theory was later shown by Gor’Kov [5] to be derivable within the framework of BCS theory. It is generally applicable to both type-I and -II superconductors close to their critical temperatures, although it is sometimes successfully applied to situations much below this. From it arise two material-specific equations that are important to the superconductor choice in many quantum technologies:
To me, arise feels a bit more natural here since I'm talking about one theory and so I feel this should take a singular verb, although Grammarly seems insistent that this should be arises (presumably due to the object being plural). Could someone please clarify which I should be using and why?