Explain the differential of lagrangian is a perfect ?L dt

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Discussion Overview

The discussion revolves around the differential of the Lagrangian and its characterization as a perfect differential, specifically in the context of classical mechanics and the action principle.

Discussion Character

  • Technical explanation, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant asks how to explain that the differential of the Lagrangian is a perfect differential.
  • Another participant states that the action differential is defined as dS = Ldt, suggesting it is a matter of definitions.
  • A different participant seeks a proof that the differential is indeed a perfect differential.
  • In response, another participant asserts that it is a perfect differential by definition.

Areas of Agreement / Disagreement

Participants express differing views on the nature of the differential, with some asserting it is a perfect differential by definition while others seek a proof or explanation for this characterization. The discussion remains unresolved.

Contextual Notes

There are limitations in the definitions and assumptions regarding what constitutes a perfect differential, which are not fully explored in the discussion.

eman2009
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how we can explain the differential of lagrangian is a perfect ?L dt
 
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It's dS = Ldt, the action differential. It's just definitions.
 


yes, but how we can prove is it a perfect differential!
 


By definition - it is.
 

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