منابع مشابه
Mystery of Point Charges
We discuss the problem of finding an upper bound for the number of equilibrium points of a potential of several fixed point charges in Rn. This question goes back to J. C. Maxwell and M. Morse. Using fewnomial theory we show that for a given number of charges there exists an upper bound independent of the dimension, and show it to be at most 12 for three charges. We conjecture an exact upper bo...
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We investigate the possible existence of nonradiating motions of systems of point charges, according to classical electrodynamics with retarded potentials. We prove that two point particles of arbitrary electric charges cannot move for an infinitely long time within a finite region of space without radiating electromagnetic energy. We show however with an example that nonradiating accelerated m...
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We investigate, from the point of view of classical electrodynamics with retarded potentials, the possible existence of nonradiating motions of point charges. We give a rigorous proof of the fact that two point particles of arbitrary electric charges cannot move for arbitrarily long times within a finite region region of space without radiating electromagnetic energy.
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Many charged macro- or supramolecular systems, such as DNA, are approximately rod-shaped and, to the lowest order, may be treated as continuous line charges. However, the standard method used to calculate electrostatics in molecular simulation, the Ewald summation, is designed to treat systems of point charges. We extend the Ewald concept to a hybrid system containing both point charges and con...
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ژورنال
عنوان ژورنال: Acta Crystallographica Section A Foundations and Advances
سال: 2014
ISSN: 2053-2733
DOI: 10.1107/s2053273314090263