Perturbative Approach to Higher Derivative and Nonlocal Theories
نویسندگان
چکیده
We propose a perturbative approach to deal with Lagrangians with higher or infinite order time derivatives. It enables us to construct a consistent Poisson structure and Hamiltonian with only first time derivatives order by order in coupling. To the lowest order, the Hamiltonian is bounded from below whenever the potential is. We consider spacetime noncommutative field theory as an example.
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تاریخ انتشار 2001