Are Canonical Transformations the Key to Understanding Hamiltonian Dynamics?

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In summary, the conversation is discussing canonical transformations, which are transformations of coordinates and momenta that preserve the Hamiltonian form of equations of motion. It is shown that a transformation is canonical if and only if the Poisson's bracket between the new coordinates and momenta is equal to the Kronecker delta. There are two sets of transformations, one that satisfies this condition and also has a new Hamiltonian and function F, and another that satisfies the Hamiltonian equations of motion but may not have a new Hamiltonian. The link between these two sets of transformations is still unclear.
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I have a system described by the hamiltonian H in the coordinates [itex]i, p_i [/itex]. A transformation of the type
$Q_i = Q_i(q_i, p_i)$ is called "canonical" if exists a new Hamiltonian, say K(Q,P), and a function F(Q_i,P_i,q_i,p_i) such that is verified

[itex]p\dot q_i-H=P_i\dot Q_i-K+\frac{dF}{dt}[/itex]

How can i prove that a trasformation is canonical (in this sense) if and only if
[itex]\{Q_i,P_j\}=\delta_{ij}[/itex]
when {} are the Poisson's braket?

I'd wish to understand another thing regardind that. I found a derivation that shows that is sufficient that is been conserved the hamiltonian form of equations of motion to conserve poisson brakets...but we know that the transformations satisfing 1). are not the unique to conserve the hamiltonian form of eq. of motion...so, what is the link between these 2 sets of trasformations?

SETS 1. Trasformations such that exists K, and F t.c. the eq. 1). is satisfied.
SETS 2. Trasformations such that exists K satisfing the equation of motion of Hamilton:
[itex] \dot Q = \frac{\partial K}{\partial P}\\ \dot P = -\frac{\partial K}{\partial Q}[/itex]
 
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What are canonical transformations?

Canonical transformations are mathematical transformations used in classical mechanics to change coordinates and momenta while preserving the underlying structure of the system. They are commonly used to simplify the equations of motion and find new coordinates that make the problem easier to solve.

What is the significance of canonical transformations?

Canonical transformations are significant because they allow us to simplify the equations of motion and find new coordinates that make the problem easier to solve. They also preserve the Hamiltonian and therefore the physical properties of the system, making them useful in studying the dynamics of a system.

What are the two types of canonical transformations?

The two types of canonical transformations are point transformations and generating function transformations. Point transformations directly change the coordinates and momenta, while generating function transformations use a generating function to make the transformation.

How do canonical transformations relate to Hamilton's equations?

Canonical transformations are closely related to Hamilton's equations of motion. They preserve the Hamiltonian and therefore the equations of motion, making them useful in solving classical mechanics problems.

What are some examples of canonical transformations?

Some examples of canonical transformations include the transformation from Cartesian to spherical coordinates, the transformation from Cartesian to cylindrical coordinates, and the transformation from position and momentum to action-angle coordinates.

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