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kilokhan
Oct12-08, 12:09 PM
Is there a commutation relation between x^{\mu} and \partial^{\nu} if you treat them as operators? I think I will need that to prove this

[$J J^{\mu \nu}, J^{\rho \sigma}] = i (g^{\nu \rho} J^{\mu \sigma} - g^{\mu
\rho} J^{\nu \sigma} - g^{\nu \sigma} J^{\mu \rho} + g^{\mu \sigma} J^{\nu
\rho})$

Where the generators are defined as



$J J^{\mu \nu} = i (x^{\mu} \partial^{\nu} - x^{\nu} \partial^{\mu})$

kilokhan
Oct12-08, 01:40 PM
Never mind, I found the appropriate relation, \partial_{\mu}x^{\nu}=g^{\mu \nu}

But I'm not entirely sure why this is true. If someone could explain that would be great.