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### Symmetry modulo total derivative term in Noether's Theorem

I came across the proof of Noether's Theorem in David Tong's notes (page 14) on QFT. He writes something like, We say that the transformation $$\delta\phi(x) = \chi (\phi) \tag{1.34}$$ is a ...
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### Srednicki chapter 22: continuous symmetries and conserved current

In Srednicki's book he says that: The Noether current plays a special role if we can find a set of infinitesimal field transformations that leaves the lagrangian unchanged, or invariant. In this ...
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### Derivation of Noether's Theorem

I have a question concerning the derivation of Noether's theorem in Peskin & Schroeders introduction to QFT. Below is a picture of the first part of it. The proof then proceeds by saying that one ...
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### How do I tell if a symmetry is gauge or not?

I understand the interpretation given in topics like this one that gauge symmetries are "fake" in the sense that they do not represent an actual difference in physical states. I also know that gauge ...
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### Scalar field in curved spaces

How do we find the energy momentum tensor as Noether charge for translations in curved spaces. This should still exist since the action is still an integral over space such that it it invariant under ...
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### What constitutes a symmetry for Noether's Theorem?

I have some confusion over what exactly constitutes a symmetry when trying to apply Noether's theorem. I have heard both that a symmetry in the action gives a conserved quantity, and that a symmetry ...
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### Big puzzle about Noether's theorem of coordinate transformation (spacetime symmetry)

For Noether theorem with only internal symmetry, I've found there has been a very clear proof. But I still struggle with the proof of coordinate transformation. Because there are so many different ...
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### Understanding this phrasing of a conserved current in QFT

I'm trying to derive a version of Noether's theorem. I found this online and I'm really confused as to what's going on on page 202 (the second slide in the link). I'll start off by saying I am ...
Suppose we have a Lagrangian that with fields that are acted on by a symmetry group, e.g. $$\mathcal{L} = \partial_{\mu}\phi \partial^{\mu}\phi^* - m^2 \phi \phi^*$$ with $G=U(1)$ (i.e. \$\phi \to e^{i ...