Is Angular Momentum Always Conserved with a Rotation-Invariant Lagrangian?

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Angular momentum conservation is linked to the invariance of the Lagrangian under rotations, as established by Noether's theorem. This principle holds true in general, provided that the system is subject to certain conditions, such as the absence of external torques. Infinitesimal rotations must be considered to ensure the validity of the conservation law. While the theorem applies broadly, specific scenarios may impose additional restrictions. Overall, angular momentum is conserved when the Lagrangian is rotation-invariant, assuming the necessary conditions are met.
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I have this question here from last year's exam that goes

"Use Noether's theorem to show that the angular momentum is conserved when the lagrangian is invariant under rotations."

I just want to know if this is true in the most general case, or if there are some restrictions somewhere not mentioned in the question.

Thank you.
 
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Yes, you'd have to check for infinitesimal rotations.
 
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