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Near-field Analysis of Superluminally Propagating Electromagnetic and Gravitational Fields

William D. Walker
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Abstract

A near-field analysis based on Maxwells equations is presented which indicates that the fields generated by both an electric and a magnetic dipole or quadrapole, and also the gravitational waves generated by a quadrapole mass source propagate superluminally in the nearfield of the source and reduce to the speed of light as the waves propagate into the farfield. Both the phase speed and the group speed are shown to be superluminal in the nearfield of these systems. Although the information speed is shown to differ from group speed in the nearfield of these systems, provided the noise of the signal is small and the modulation method is known, the information can be extracted in a time period much smaller than the wave propagation time, thereby making the information speed only slightly less than the superluminal group speed. It is shown that relativity theory indicates that these superluminal signals can be reflected off of a moving frame causing the information to arrive before the signal was transmitted (i.e. backward in time). It is unknown if these signals can be used to change the past.

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William D. Walker. 2003-04-23. Near-field Analysis of Superluminally Propagating Electromagnetic and Gravitational Fields. https://arxiv.org/abs/gr-qc/0304090

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