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In 1975, Ashtekar and Magnon showed that anenergy condition selects a unique quantization procedurefor hypersurface orthogonal observers in general, curvedspacetimes. We generalize this result in two important ways, by eliminating the need toassume a particular form for the (quantum) Hamiltonian,and by considering the surprisingly nontrivial extensionto non-minimal coupling, for which the classical Hamiltonian differs from the classical energycalculated from the stress-energy tensor. 相似文献
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Carlos A. López 《General Relativity and Gravitation》1997,29(9):1095-1098
It is shown that uncharged test particles, released from rest at infinity in the Kerr-Newman field, stop and rebound when the radial coordinate r takes the value r0 = Q2/(2M). This expression corresponds to the position of a stationary source of the Kerr-Newman field found by the author. It represents the surface of a massive oblate ellipsoid of revolution undergoing rigid rotation. Besides, the magnitude of r0 guarantees that no violation of causality occurs throughout spacetime. Although the test particles' angular momenta are always zero, they acquire a rotational motion as a consequence of the dragging of inertial frames. 相似文献
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内南五味子化学成分的研究 总被引:7,自引:0,他引:7
从内南五味子的茎藤中分得七个化合物, 经波谱和X衍射分析, 其中五广系一类新型的螺环衍生物木脂素, 分别定名为内南五味子素(3), 内南五味子素乙(4), 丙(5),J(6)及异内南五味子素(7), 另外两个已知化合物为南五味子素和β-谷甾醇。 相似文献
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本文报道了七个新的2,4,5-三氧-1,3,2,4-二氮二磷杂环戊烷衍生物的制备, 产物的结构经IR, ^1H和^31P NMR, MS以及元素分析证实, 并利用^31P NMR和GC-MS区分了化合物的顺式和反式异构体。 相似文献