v 1 2 2 A ug 1 99 7 quant - ph / 9708037 Moments of the Wigner Distribution and a Generalized Uncertainty Principle
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چکیده
The nonnegativity of the density operator of a state is faithfully coded in its Wigner distribution, and this places constraints on the moments of the Wigner distribution. These constraints are presented in a canonically invariant form which is both concise and explicit. Since the conventional uncertainty principle is such a constraint on the first and second moments, our result constitutes a generalization of the same to all orders. Possible application in quantum state reconstruction using optical homodyne tomography is noted.
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تاریخ انتشار 2008