Noether's theorem for finite Hamiltonian systems

In summary, the Noether's theorem for finite Hamiltonian systems states that if you know a symmetry, you can write the first integral by using the vector field generated by the symmetry. This can be achieved by putting the vector field of the arbitrary function equal to the Poisson bracket of the function and the Hamiltonian. To apply this theorem, you must have knowledge of the metric and the Hamiltonian, and then look for a symmetry. Once a symmetry is found, the Noether's theorem can be used to obtain the first integral. However, the proof for this case may be difficult to understand.
  • #1
thaalves
2
0
TL;DR Summary
How do I write a first integral knowing a symmetry?
The Noether's theorem for finite Hamiltonian systems says that:

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My question is: If I know a symmetry how can I write the first integral?
 
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  • #2
If ##\mathbf{w}## is the vector field generating the symmetry then I think you can put ##\mathbf{w}(f) = \{ f, P \}## for an arbitrary function ##f##?
 
  • #3
In fact my knowledge is very limited in this area, my situation is as follows...
I have the metric, with the metric I can write the Hamiltonian, with the Hamiltonian, can I write the field? if yes, after that do i have to look for a symmetry? Apparently once I have symmetry, Noether's theorem gives me the first integral (his proof in this case), but I'm not getting it.
 

FAQ: Noether's theorem for finite Hamiltonian systems

What is Noether's theorem for finite Hamiltonian systems?

Noether's theorem for finite Hamiltonian systems is a mathematical principle in classical mechanics that relates the symmetries of a physical system to its conserved quantities. It states that for every continuous symmetry of a system, there exists a corresponding conserved quantity.

How does Noether's theorem apply to finite Hamiltonian systems?

Noether's theorem applies to finite Hamiltonian systems by identifying the symmetries of the system and using them to determine the conserved quantities. These conserved quantities can then be used to understand the dynamics of the system and make predictions about its behavior.

What are some examples of finite Hamiltonian systems?

Some examples of finite Hamiltonian systems include a pendulum, a spinning top, and a simple harmonic oscillator. These systems have a finite number of degrees of freedom and can be described by a set of equations known as Hamilton's equations.

Are there any limitations to Noether's theorem for finite Hamiltonian systems?

Yes, there are some limitations to Noether's theorem for finite Hamiltonian systems. It only applies to systems with a finite number of degrees of freedom and does not account for dissipative forces or external perturbations.

How is Noether's theorem used in practical applications?

Noether's theorem is used in practical applications to understand the underlying symmetries of physical systems and to determine conserved quantities. It has been applied in various fields such as mechanics, electromagnetism, and quantum mechanics to make predictions and solve problems.

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