  This paper deals with the Berry phase, and the ontology of the
electromagnetic vector potential. When the state of the system is gauge
symmetric, the vector potential may be interpreted as a convenient tool of a
mathematical formulation, with no ontological meaning.
  I argue that this interpretation is in difficulty because the vector
potential depends linearly on the supercurrent in the superfluid state, which
is a spontaneously broken gauge symmetry state, where particle number is not
conserved. I suggest that when gauge symmetry is spontaneously broken, the
vector potential becomes an emergent material object of nature. The revised
version includes sections on scientific realism, and emergence, and new
references on Noether's theorem, among others.
