Once Ive asked here why you physicist use Gauge theories with such confidence and the overall answer was "because it works". This probably is true but perhaps is also a bit disappointing to me because I was looking something more fundamental. Ive recently thought of something that may be the answer I was looking but I want to share it with you because your opinions / corrections are always very helpful:(adsbygoogle = window.adsbygoogle || []).push({});

Noether Theorem says that for every symmetry there is a global conserved charge. When the symmetry is local (the parameter varies from spacetime to spacetime) is like having an infinite number of symmetries (one for each point of spacetime) and that says that there is an infinite number of conserved charges. (one for each point of spacetime). This (with a bit of imagination or a bit of math) can be interpretated as if there is only one conserved charge but that this conservations applies not only globally but also locally in every point of spacetime.

So if we want a Lagrangian to describe a local conservation of charge, then, the only way to do it is by using a gauge theory.

Am I too wrong? Cant we use this idea to give a theoretical reason on using Gauge Theories and to explain why theyve been so successful?

Thanks in advance for your answers.

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# On the use of Gauge Theories

**Physics Forums | Science Articles, Homework Help, Discussion**