Canonical Transformations, Poisson Brackets

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SUMMARY

This discussion centers on the application of canonical transformations in classical mechanics, specifically regarding the Hamiltonian formulation. It establishes that the transformed momentum P is canonically conjugate to the transformed coordinate Q, supported by the properties of Poisson brackets. The Poisson brackets for the original and transformed variables are shown to be conserved, with values of either 0 or 1, confirming the relationship between the variables remains intact during the transformation.

PREREQUISITES
  • Understanding of Hamiltonian mechanics
  • Familiarity with canonical transformations
  • Knowledge of Poisson brackets
  • Basic concepts of classical mechanics
NEXT STEPS
  • Study the properties of Poisson brackets in detail
  • Explore examples of canonical transformations in classical mechanics
  • Learn about the implications of Hamiltonian dynamics
  • Investigate the relationship between canonical transformations and symplectic geometry
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Students of classical mechanics, physicists specializing in Hamiltonian systems, and anyone interested in the mathematical foundations of canonical transformations and Poisson brackets.

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This isn't actually a homework problem, but a problem from a book, but as it's quite like a homework problem I thought this forum was probably the best place for it.

Homework Statement



Consider a system with one degree of freedom, described by the Hamiltonian formulation of classical mechanics in terms of the coordinate q, and the canonically conjugate momentum, p. A canonical transformation is applied, such that the transformed Hamiltonian is described in terms of the transformed coordinate Q and the transformed momentum P. Explain whether P will be canonically conjugate to Q, and how Poisson brackets may be used to check this.

Homework Equations





The Attempt at a Solution



P will be canonically conjugate to Q (it says so in a book!) and possibly that Poisson brackets will give a constant value (books seem to suggest either 0 or 1?). If anyone can explain this further I'd really appreciate it!

Thanks
 
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As far as I remember, we have for a canonical transformation
\{q,p\}=\{Q,P\}=0,
and
\{q,q\}=\{Q,Q\}=\{p,p\}=\{P,P\}=1,
i.e. the Poisson brackets are conserved in a canonical transformation.

Even if this property isn't directly mentioned, I found the wiki article on canonical transformations quite good: http://en.wikipedia.org/wiki/Canonical_transformation"

I guess the fact that the Poisson brackets are conserved is a consequence of the fact that the dynamics aren't changed in a canonical transformation.
 
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