Hamiltonian as the generator of time translations

AI Thread Summary
The Hamiltonian is identified as the generator of time translations due to its role in the evolution of a system's state over time, as expressed in the equation for the time derivative of a function F(q,p). This relationship is derived from the Poisson bracket, where if F is not explicitly time-dependent, its time evolution is solely determined by the Hamiltonian. The discussion also references Noether's theorem, which connects symmetries and conservation laws in physics. For further understanding, Susskind's classical mechanics lectures on YouTube are recommended. The concept emphasizes the fundamental link between Hamiltonian dynamics and time evolution in classical mechanics.
Frank Castle
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In literature I have read it is said that the Hamiltonian ##H## is the generator of time translations. Why is this the case? Where does this statement derive from?

Does it follow from the observation that, for a given function ##F(q,p)##, $$\frac{dF}{dt}=\lbrace F,H\rbrace +\frac{\partial F}{\partial t}$$ In particular, if ##F## is not explicitly dependent on time, then $$\frac{dF}{dt}=\lbrace F,H\rbrace $$ Or is there more to it?
 
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Ah poisson brackets!

I think what you are looking for is Noethers theorem.

Susskinds classical mechanics course on youtube, i think lecture 4 (symmetries) and 8 (poisson) will help you.
 
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