Skip to main content
Physics

You are not logged in. Your edit will be placed in a queue until it is peer reviewed.

We welcome edits that make the post easier to understand and more valuable for readers. Because community members review edits, please try to make the post substantially better than how you found it, for example, by fixing grammar or adding additional resources and hyperlinks.

6
  • 1
    $\begingroup$ Ok, so I can consider it just a mere mathematical artifact useful to make calculations? $\endgroup$
    – JackI
    Commented Dec 8, 2017 at 17:34
  • 1
    $\begingroup$ I don't think this is correct in the case of nonabelian gauge quantum field theory; see my answer. $\endgroup$
    – tparker
    Commented Dec 8, 2017 at 17:55
  • $\begingroup$ @tparker OP is asking explicitly about electromagnetism, which is immune from any nonabelian subtleties. $\endgroup$
    – Emilio Pisanty
    Commented Dec 8, 2017 at 18:06
  • $\begingroup$ @EmilioPisanty Yes, but Qmechanic's original answer didn't have that caveat, and so ran the risk of being interpreted as applying to all gauge theories, including nonabelian. $\endgroup$
    – tparker
    Commented Dec 9, 2017 at 16:01
  • $\begingroup$ @Qmechanic Doesn't the restriction that you state in your first footnote make your updated answer vacuous? You're now just saying that for the class of gauge theories for which gauge transformations are unphysical, gauge transformations are unphysical. This is true but tautological. $\endgroup$
    – tparker
    Commented Dec 9, 2017 at 16:08