Sorry,I am new to this topic,and I still confuse about some details.
Here is what I realize: U(1) symmetry correspond to conservation of electric charge,so the physics meaning of "U(1)" in this model is to make sure that the charge of the complex scalar field is conservative.
Am I right?
1.In Abelian higgs model,we can come to the results that the gauge bosons acquire mass, implying the photons also acquire mass in this model；however,photons are massless in reality.How to explain this dilemma?
2.What does U(1) mean in this model?Does it correspond to some coservation laws,or...
hi~I am a beginner of Gauge theories,and I have some questions~
Why we need loacal phase invariance?
Because i cannot understand why we assume phase depend on the position.Is there any theory leading to this asssumption?