Relativistic angular momentum and cyclic coordinates

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maverick_starstrider
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I'm getting myself confused here. If my relativistic Lagrangian for a particle in a central potentai is

[tex]L = \frac{-m_0 c^2}{\gamma} - V(r)[/tex]

should

[tex]\frac{d L}{d \dot{\theta}}[/tex]

not give me the angular momentum (which is conserved)? Instead I get

[tex]\frac{d L}{d \dot{\theta}} = -4 m v r^2 \dot{\theta}\gamma[/tex]
 
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[tex]L = - {m_0}{c^2}\sqrt {1 - \frac{{{{\dot r}^2} + {r^2}{{\dot \theta }^2}}}{{{c^2}}}} - V\left( r \right)[/tex]

so

[tex]\frac{{\partial L}}{{\partial \dot \theta }} = \gamma {m_0}{r^2}\dot \theta[/tex]

What's the problem?
 
Absolutely nothing apparently. I just did it again this morning and got the right answer. Sorry for the time waste.