0

I am wondering if the masslessness of photons is due to the local gauge invariance of $u(1)$-gauge fields. The reason why I consider about this question is that I remember that the Proca field is not locally $u(1)$-invariant. How do I prove this explicitly in field theory?

Qmechanic
  • 201,751
Xiaoyi Jing
  • 1,068

0 Answers0