If we have the Einstein Lagrangian...[tex] L= \sqrt (-g)R [/tex] my question is how do you get the Hamiltonian?..the approach by Wheeler-De Witt is to consider the line element:(adsbygoogle = window.adsbygoogle || []).push({});

[tex] ds^2 = N(t)dt^^2 + g_ij dx^i dz^ j [/tex] (Einstein sum convention) and then substitute it into the Lagrangian above and perform a Legendre transform in the form:

[tex] \pi_ij \dot g_ij -L [/tex] where "pi2 are the momenta.

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# Einstein Hamiltonian

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