Derivation in classical mechanics

AI Thread Summary
The discussion centers on the confusion surrounding the various differential identities in classical mechanics related to action, Hamiltonian, Lagrangian, kinetic energy, and potential energy. The original poster questions whether additional relationships exist beyond the basic ones and seeks examples for clarification. Respondents emphasize that while these identities can be derived from the Hamiltonian or Lagrangian, they are not necessary for solving equations of motion. They also express frustration at the request for extensive examples, indicating that the poster should engage more deeply with the material. The thread concludes with a suggestion to end the discussion.
Jhenrique
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I'm studying classical mechanics and I'm stumbling in the quantity of differential identities.

Being S the action, H the hamiltonian, L the lagrangian, T the kinetic energy and V the potential energy, following the relationships:

attachment.php?attachmentid=70623&stc=1&d=1402838216.png


But, the big question is: that's all? Or has exist more?

Seems be missing
$$\frac{\partial S}{\partial q'} \;\;\; \frac{\partial S}{\partial p} \;\;\; \frac{\partial S}{\partial p'} \;\;\; \frac{\partial S}{\partial q'} \;\;\; \frac{\partial L}{\partial p} \;\;\; \frac{\partial L}{\partial p'} \;\;\; \frac{\partial H}{\partial p'} \;\;\; \frac{\partial H}{\partial q'} \;\;\; \frac{\partial V}{\partial q'} \;\;\; \frac{\partial V}{\partial p} \;\;\; \frac{\partial V}{\partial p'} \;\;\; \frac{\partial T}{\partial q} \;\;\; \frac{\partial T}{\partial p} \;\;\; \frac{\partial T}{\partial p'}$$
These relation exist? Make sense? If yes, how will be the identities?
 

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Once you write down the Hamiltonian or the Lagrangian then you certainly can write down all of the rest of those quantities, but there is no point it doing so. You can already solve the equations of motion without them.
 
DaleSpam said:
Once you write down the Hamiltonian or the Lagrangian then you certainly can write down all of the rest of those quantities

How? Give me examples...
 
First, it's please give me examples. We are not your servants, to be ordered around.

Second, you're essentially asking us to write down a textbook for you. I'm afraid that's beyond what one can reasonably expect PF to do. You are going to have to do some work on your own.

This looks like a good time to close this thread.
 
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