Superluminal Signal Velocity
نویسنده
چکیده
It recently has been demonstrated that signals conveyed by evanescent modes can travel faster than light. In this report some special features of signals are introduced and investigated, for instance the fundamental property that signals are frequency band limited. Evanescent modes are characterized by extraordinary properties: Their energy is negative, they are not directly measurable, and the evanescent region is not causal since the modes traverse this region instantaneously. The study demonstrates the necessity of quantum mechanical principles in order to interprete the superluminal signal velocity of classical evanescent modes.
منابع مشابه
Superluminal signals: an engineer’s perspective
Recent experiments with evanescent waveguide modes demonstrated the existence of superluminal group velocities. The still ongoing debate concerning the definition of an appropriate signal velocity is revisited, and a case study of a raised cosine signal is presented to investigate the practical relevance of superluminal signals. 2001 Elsevier Science B.V. All rights reserved. PACS: 41.20.Jb; ...
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