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Q is a conserved charge if \{Q, H\} = 0
Show that q+\epsilon\delta q satisfies the equation of motion.
\delta q = \{q, Q\}
I couldn't find the proof. Anybody knows?
My workings:
\delta q = \{q, Q\}
\delta\dot{q} = \{\{q,Q\},H\} = - \{\{Q,H\},q\} - \{\{H,q\},Q\}
\delta\dot{q} = \{\{q,Q\},H\} = \{\{q,H\},Q\}
\delta\dot{q} = \{\{q,Q\},H\} = \{\dot{q},Q\}
Let q' = q+\epsilon\delta q
Show that \dot{q'} = \{q,H\}|_{q'}
L.H.S. is \dot{q}+\epsilon\delta\dot{q}
R.H.S is \{q,H\}+\epsilon\partial_q\{q,H\}\delta q
Therefore we have to prove \{\dot{q},Q\} = \partial_q\{q,H\}\{q,Q\}
...
No clue how to continue
Show that q+\epsilon\delta q satisfies the equation of motion.
\delta q = \{q, Q\}
I couldn't find the proof. Anybody knows?
My workings:
\delta q = \{q, Q\}
\delta\dot{q} = \{\{q,Q\},H\} = - \{\{Q,H\},q\} - \{\{H,q\},Q\}
\delta\dot{q} = \{\{q,Q\},H\} = \{\{q,H\},Q\}
\delta\dot{q} = \{\{q,Q\},H\} = \{\dot{q},Q\}
Let q' = q+\epsilon\delta q
Show that \dot{q'} = \{q,H\}|_{q'}
L.H.S. is \dot{q}+\epsilon\delta\dot{q}
R.H.S is \{q,H\}+\epsilon\partial_q\{q,H\}\delta q
Therefore we have to prove \{\dot{q},Q\} = \partial_q\{q,H\}\{q,Q\}
...
No clue how to continue