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formalisms:hamiltonian_formalism [2018/04/13 11:34]
bogumilvidovic [Why is it interesting?]
formalisms:hamiltonian_formalism [2023/04/02 03:34] (current)
edi [Concrete]
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 ====== Hamiltonian Formalism ====== ====== Hamiltonian Formalism ======
    
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 <tabbox Intuitive> ​ <tabbox Intuitive> ​
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  ​$$H ​ \equiv \sum_j {\dot q}_j p_j  - L$$  ​$$H ​ \equiv \sum_j {\dot q}_j p_j  - L$$
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 +----
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 +**Graphical Summary of Newtonian, Lagrangian, and Hamiltonian Formalism**
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 +[{{ :​frameworks:​newton_lagrange_hamilton.jpg?​nolink }}]
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 +For some concrete examples worked out in all three frameworks see [[https://​esackinger.wordpress.com/​blog/​classical-mechanics|Fun with Symmetry]].
  
  
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 <tabbox Why is it interesting?> ​ <tabbox Why is it interesting?> ​
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-<​blockquote>​[E]verybody loves Hamilton’s equations: there are just two, and they summarize the entire essence of classical mechanics. 
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-<​cite>​[[https://​johncarlosbaez.wordpress.com/​2012/​01/​19/​classical-mechanics-versus-thermodynamics-part-1/​|John Baez]]</​cite></​blockquote>​ 
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 <​blockquote>​In fact, <​blockquote>​In fact,
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 --> How is the Hamiltonian Formalism related to the Newtonian Formalism?# --> How is the Hamiltonian Formalism related to the Newtonian Formalism?#
  
-<​blockquote>​"Recall that we derived Hamilton’s equations for a particle moving in a force field $F = -dV/dx$ by writing down the equations of motion in the form $$ m \dot{x} =  p , \quad     ​\dot{p} = - \frac{\partial V}{\partial x} .$$  The observant reader will have noticed that these two equations are just one way to express Newton’s second law. More generally for a system of N point-like particles moving in three-dimensional physical space, Newton’s second law would be $$ m \dot{x_j} =  p_j , \quad     ​\dot{p}_j = - \frac{\partial V}{\partial x_j} .$$" ​<​cite>​The symplectic egg in classical and quantum mechanics by Maurice A. de Gosson</​cite></​blockquote>​+<​blockquote>​Recall that we derived Hamilton’s equations for a particle moving in a force field $F = -dV/dx$ by writing down the equations of motion in the form $$ m \dot{x} =  p , \quad     ​\dot{p} = - \frac{\partial V}{\partial x} .$$  The observant reader will have noticed that these two equations are just one way to express Newton’s second law. More generally for a system of N point-like particles moving in three-dimensional physical space, Newton’s second law would be $$ m \dot{x_j} =  p_j , \quad     ​\dot{p}_j = - \frac{\partial V}{\partial x_j} .$$ <​cite>​The symplectic egg in classical and quantum mechanics by Maurice A. de Gosson</​cite></​blockquote>​
  
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formalisms/hamiltonian_formalism.1523612095.txt.gz · Last modified: 2018/04/13 09:34 (external edit)