What is the Precise Heuristic Argument that Leads to Noether's Theorem

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Noether's theorem states that every continuous symmetry of a Lagrangian corresponds to a conserved quantity. The discussion highlights confusion regarding the precise interpretation and presentation of the theorem in literature. A participant emphasizes the importance of including time in discussions of symmetries, even when using simplified analogies. The conversation suggests that a more elementary treatment of the theorem could clarify its implications. Overall, the precise heuristic argument revolves around the relationship between symmetries and conservation laws in physics.
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Hi,
I'm confused about the exact interpretation of Noether's theorem for fields. I find that the statement of the theorem and its proof are not presented in a precise manner in books.
My main question is: what is the precise heuristic argument that leads to Noether's theorem?

The question is presented in the attached pdf document.

Thanks
 

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what is the precise heuristic argument that leads to Noether's theorem?
precise argument is that any continuous symmetry of lagrangian i.e. which can be build up from infinitesimal ones implies a conserved quantity.Also you have forgotten the action in your two dimensional case i.e. where is time?
 
I excluded time because I used a 2D space analogy, which was easy to illustrate in a figure. I'm interested in the idea, so it doesn't matter if I use time or not.
 
Topic about reference frames, center of rotation, postion of origin etc Comoving ref. frame is frame that is attached to moving object, does that mean, in that frame translation and rotation of object is zero, because origin and axes(x,y,z) are fixed to object? Is it same if you place origin of frame at object center of mass or at object tail? What type of comoving frame exist? What is lab frame? If we talk about center of rotation do we always need to specified from what frame we observe?

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