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Analysis of Causality Issue in Near-field Superluminally Propagating Electromagnetic and Gravitational Fields

William D. Walker
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Abstract

A simple relativistic analysis is presented which shows that near-field superluminal longitudinal electric signals generated by an electric dipole cannot be used to violate Einstein causality by using the relativistic "sync shift" effect. The analysis shows that because a signal has some time extent (i.e. after a signal is initiated one must waitat least one period for the frequency and amplitude information to be determined), an electric dipole can be used to transmit a signal backward in time, but not before the same signal was initiated, thereby prohibiting a user from changing the signal that was transmitted. The result is also shown to apply to the superluminal near-field gravitational fields generated by an oscillating mass.

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William D. Walker. 2000-09-26. Analysis of Causality Issue in Near-field Superluminally Propagating Electromagnetic and Gravitational Fields. https://arxiv.org/abs/physics/0009076

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