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Anomalous microwave propagation in open space
Abstract
It has been observed in the far radiating zone that at a certain receiver antenna position and orientation the transit time of the arriving pulse-modulated microwaves in open space was constant regardless of the distance between the receiver and the transmitter. The apparent phase velocity exceeded the intrinsic velocity. Calibration techniques employed and repeated time-domain measurements done at different frequencies and distances confirmed this phenomenon.
... Various experimental researches have been carried out on superluminal phenomena in recent years, which include the barrier tunneling of photons [1,2], superluminal microwave tunneling through undersized waveguide [3,4], superluminal experiments of microwave in open space5678, microwave traversing double-prism91011, light or electromagnetic pulses traveling through anomalous dispersion region1213141516. For a review of superluminal issue, see [17]. ...
... The radiant component must be suppressed in order to make superluminal propagation evident. In the experimental setup of [5], mis-alignment of the receiving antenna makes the evanescent wave component dominated, as shown inFig. 3. ...
... On the other hand, the distance between the two antenna walls is smaller compared to the case ofFig. 3(a), so superluminal phenomenon can be observed at a larger distance of , just as indicated by the experimental result in [5]. In fact, when the two antennae are placed face to face, there will also exist tunneling of evanescent wave. ...
An explanation for superluminal phenomena based on wave-particle duality of photons is suggested. A single photon may be regarded as a wave packet, whose spatial extension is its coherence volume. As a photon propagates as a wave train in vacuum, its velocity is just the speed of light. When it tunnels through a barrier as a particle, its wave function collapses and it will travel faster than light. Superluminal propagation can occur only within the coherence length and the time constrained by uncertainty principle. A massive particle cannot be superluminal during the tunneling process. So superluminality does not violate causality. As for the superluminal and negative group velocities in anomalously dispersive medium, they are merely reshaping effect of the pulse, and they will become subluminal at large distances. A couple of experiments are proposed to test the superluminal phenomena.
... Hamilton operators (146) and (186). But what is surprising is that both these Hamiltonians led to practically coinciding S-matrices, at least in the lowest orders of perturbation theory. ...
... Salviati. Superluminal eects in the propagation of electromagnetic elds have also been found in a number of other experiments [186,187,188]. ...
Sagredo, Salviati, Simplicio and their friends debate relativity, quantum mechanics, quantum field theory and quantum gravity
... In the former paper the scalar potential waves were emitted by the spherical antenna. Longitudinal electric waves were observed in air [3]. Longitudinal electrodynamic forces, observed in [14], and longitudinal Ampere forces in [5] could be due to the proposed longitudinal electric waves. ...
In this work by using the assumptions that wavelength is much smaller than charge separation distance of an electric dipole, which in turn is much smaller than a distance up to the point of observation, the new results for radiation of an electric dipole were obtained. These results generalize and extend the standard classical solution, and they indicate that under the above assumptions the electric dipole emits both long-range longitudinal electric and transverse electromagnetic waves. For a specific values of the dipole system parameters the longitudinal and transverse electric fields are displayed. Total power emitted by electric and electromagnetic waves are calculated and compared. It was shown that under the standard assumption of charge separation distance being much smaller than wavelength: a) classical solution correctly describes the transverse electromagnetic waves only; b) longitudinal electric waves are non-negligible; c) total radiated power is proportional to the fourth degree of frequency and to the second degree of the charge separation distance; d) transverse component of our solution reduces to classical solution. In case wavelength is much smaller than charge separation distance: a) the classical solution is not valid and it overestimates the total radiated power; b) longitudinal electric waves are dominant and transverse electromagnetic waves are negligible; c) total radiated power is proportional to the third degree of frequency and to the charge separation distance; d) most of the power is emitted in a narrow beam along the dipole axis, thus emission of waves is focused as with lasers.
... Longitudinal vector potential waves were observed in [52,53,31,46]. Longitudinal electric waves in open air were experimentally observed in [18,16,14,15]. The experiments were performed in the microwave region with 8.245 and 12.25 GHz frequencies using the waveguides, an electric dipole and a magnetic dipole. ...
In this paper, radiation due to standing wave currents were considered for the electric dipole. Assumptions that wavelength is much smaller than the dipole separation distance, which is in turn much smaller than the distance to the point of observation, were employed. Results indicate that the electric dipole, which now essentially is a linear antenna, emits both long range longitudinal electric and transverse electromagnetic waves. Two cases were considered: electric dipole with and without charge oscillations at its ends. Each case was further divided into two cases: with even and odd number of half-wavelengths. For specific values of the system, longitudinal electric and transverse electromagnetic waves, total radiated power, longitudinal to transverse power ratio and radiation resistance were calculated and depicted.
... In the former paper the scalar potential waves were emitted by the spherical antenna. Longitudinal electric waves were observed in air (Glakos & Ishii, 1991). Longitudinal electrodynamic forces, observed in Johansson (1996), and longitudinal Ampere forces in Graneau (1984) could be due to the proposed longitudinal electric waves. ...
In this work, by using the assumptions that wavelength is much smaller than charge separation distance of an electric dipole, which in turn is much smaller than a distance up to the point of observation, the new results for radiation of an electric dipole were obtained. These results generalize and extend the standard classical solution, and they indicate that under the above assumptions, the electric dipole emits both long‐range longitudinal electric and transverse electromagnetic waves. For a specific values of the dipole system parameters, the longitudinal and transverse electric fields are displayed. Total power emitted by electric and electromagnetic waves are calculated and compared. It was shown that under the standard assumption of charge separation distance being much smaller than wavelength, (a) classical solution correctly describes the transverse electromagnetic waves only; (b) longitudinal electric waves are nonnegligible; (c) total radiated power is proportional to the fourth degree of frequency and to the second degree of the charge separation distance; and (d) transverse component of our solution reduces to classical solution. In case wavelength is much smaller than charge separation distance, (a) the classical solution is not valid, and it overestimates the total radiated power; (b) longitudinal electric waves are dominant and transverse electromagnetic waves are negligible; (c) total radiated power is proportional to the third degree of frequency and to the charge separation distance; and (d) most of the power is emitted in a narrow beam along the dipole axis; thus, emission of waves is focused as with lasers.
... The idea about electromagnetic interactions being composed of both instantaneous (bound) and retarded (radiation) parts is not new. It was repeatedly expressed theoretically [3, 4, 5], and electromagnetic superluminal effects were seen in experiments as well [6, 7, 8]. However, these ideas and experiments are usually met with scepticism, because they violate the special relativistic ban on faster-than-light propagation of signals. ...
Recent experiments, performed by Prof. Pizzella's team with relativistic electron bunches, indicate that Coulomb field is rigidly attached to the charge's instantaneous position. Despite a widespread opinion, this fact does not violate causality in moving reference frames. To see that, one should apply the Wigner – Dirac theory of relativistic dynamics and take into account that the Lorentz boost generator depends on interaction. Then one can show that interaction remains instantaneous in all reference frames.
... Perhaps the first convincing experimental observation of the superluminal character of bound electromagnetic fields was performed by Giakos and Ishii in 1991 [GI91b,GI91a]. They studied the propagation of microwave pulses between two horn antennas arranged as shown in Fig. 7.1. ...
In this second volume of the series, we build an alternative version of quantum electrodynamics, which we call relativistic quantum dynamics (RQD). The key idea of RQD is to reinterpret quantum field theory in the language of physical "dressed" particles. We also modify formulas of special relativity by taking into account the boost dependence of interactions. By doing so, we arrive at a theory where charged particles interact via instantaneous action-at-a-distance forces, there is no need for renormalization, and the Minkowski space-time unification is an approximate concept. This theory describes electromagnetic phenomena, such as the Lamb shift and the Aharonov-Bohm effect, in terms of directly interacting charges, but in full accord with fundamental principles of relativity and causality. RQD finds its strongest experimental support in the recently discovered superluminal propagation of the Coulomb field associated with relativistic electron bunches.
Measurements of tunneling times by photons possess certain advantages over those by electrons or other particles, stemming from the fact that the wavelength of visible light is larger than the de Broglie wavelength of massive particles. The types of tunnel barriers for photons used in tunneling-time experiments are (1) periodic dielectric structures excited inside their band gap or stop-band, (2) frustrated total internal reflection (FTIR) in glass or dielectric prisms, and (3) waveguides beyond cutoff. The chapter discusses the problem of superluminal group velocities, which have been predicted for the propagation of wave packets tuned to transparent spectral regions of media with inverted atomic populations. The cases of superluminal wave packets tuned close to zero frequency, and those tuned close to an atomic resonance with gain in it, are discussed further in the chapter. The new kinds of superluminal propagation effects occur over much longer distances than for tunneling.
The chapter has as main objective to clarify some important concepts appearing in relativistic spacetime theories and which are necessary of a clear understanding of our view concerning the formulation and understanding of Maxwell, Dirac and Einstein theories. Using the definition of a Lorentzian spacetime structure presented in Chap. 4 we introduce the concept of a reference frame in that structure which is an object represented by a given unit timelike vector field (). We give two classification schemes for these objects, one according to the decomposition of and other according to the concept of synchronizability of ideal clocks (at rest in ). The concept of a coordinate chart covering U and naturally adapted to the reference frame is also introduced. We emphasize that the concept of a reference frame is different (but related) from the concept of a frame which is a section of the frame bundle. The concept of Fermi derivative is introduced and the physical meaning of Fermi transport is elucidated, in particular we show the relation between the Darboux biform of the theory of Frenet frames and its decomposition as an invariant sum of a Frenet biform (describing Fermi transport) and a rotation biform such that the contraction of with the velocity field v of the spinning particle is directly associated with the so-called Pauli-Lubanski spin 1-form. We scrutinize the concept of diffeomorphism invariance of general spacetime theories and of General Relativity in particular, discuss what meaning can be given to the concept of physically equivalent reference frames and what one can understand by a principle of relativity. Examples are given and in particular, it is proved that in a general Lorentzian spacetime (modelling a gravitational field according to General Relativity) there is in general no reference frame with the properties (according to the scheme classifications) of the inertial referenced frames of special relativity theories. However there are in such a case reference frames called pseudo inertial reference frames (PIRFs) that have most of the properties of the inertial references frames of special relativity theories. We also discuss a formulation (that one can find in the literature) of a so-called principle of local Lorentz invariance and show that if it is interpreted as physical equivalence of PIRFs then it is not valid. The Chapter ends with a brief discussion of diffeormorphism invariance applied to Schwarzschild original solution and the Droste-Hilbert solution of Einstein equation which are shown to be not equivalent (the underlying manifolds have different topologies) and what these solutions have to do with the existence of blackholes in the “orthodox”interpretation of General Relativity.
By means of a small square loop antenna and an electric probe it was possible to detect significant longitudinal components of magnetic and electric fields, respectively, in the far zone in the air. Unique features of this observation are the abundance and the slow variation with radial distance of the detected longitudinal electromagnetic field components which seem to decay at a rate much slower than 1/r2. © 1993 John Wiley & sons, Inc.
An inexpensive system that accurately measures ranges of the order of meters, with the resolution of centimeters, is described. The synthesized pulse and phase counting methods, based on coherent transmission and quadrature detection, are discussed. Suitable calibration schemes to obtain distance measurement accuracies better than 99% are described. © 1993 John Wiley & sons, Inc.
The authors present theoretical aspects which characterize electromagnetic propagation of observed planewaves produced by an X -band open ended waveguide in the radiating zone, at angular offsets which are roughly the halfwidth of the beam generated by the transmitting waveguide. Elements of wave propagation are presented where the magnitude of the Poynting vector propagates with the magnitude of the intrinsic velocity in a direction of interest different from the direction of propagation of the Poynting vector of the uniform TEM (transverse electromagnetic) plane wavefront. Equations are derived which suggest that decreased energy density propagates with an energy transport velocity equal to the magnitude of the phase velocity. The theory presented here agrees with experimental observations
Abnormal velocities in passive structures such as one-dimensional (1-D) photonic crystals and a slab having a negative index of refraction are discussed. In the case of 1-D photonic crystal, the frequency- and time-domain experiments for waves tuned to the bandgap of the photonic crystal demonstrate a positive group velocity exceeding the speed of light in vacuum (superluminal). In the case of a medium with negative index of refraction, our theoretical studies show that such a medium can support positive group and negative phase velocities (backward waves), as well as negative group and negative phase velocities. The meaning of superluminal group velocity and negative group velocity, or equally, positive superluminal group delay and negative group delay, are discussed. It is shown that despite their counterintuitive meaning there are no contradictions with the requirements of relativistic causality (Einstein causality). To clearly demonstrate this, the important subject of the "front" is reintroduced.
Two historical incidents of discoveries by sincere, reputable researchers in electromagnetics that later proved to be false are recounted. It is shown how each case was finally resolved by a visit to the researcher's own laboratory. The ongoing controversy surrounding recent claims that, under certain conditions, microwave signals can travel faster than the speed of light in a vacuum is described, and such a visit is suggested.< >
This book is an attempt to build a consistent relativistic quantum theory of
interacting particles. In the first part of the book "Quantum electrodynamics"
we follow rather traditional approach to particle physics. Our discussion
proceeds systematically from the principle of relativity and postulates of
quantum measurements to the renormalization in quantum electrodynamics. In the
second part of the book "The quantum theory of particles" this traditional
approach is reexamined. We find that formulas of special relativity should be
modified to take into account particle interactions. We also suggest
reinterpreting quantum field theory in the language of physical "dressed"
particles. This formulation eliminates the need for renormalization and opens
up a new way for studying dynamical and bound state properties of quantum
interacting systems. The developed theory is applied to realistic physical
objects and processes including the hydrogen atom, the decay law of moving
unstable particles, the dynamics of interacting charges, relativistic and
quantum gravitational effects. These results force us to take a fresh look at
some core issues of modern particle theories, in particular, the Minkowski
space-time unification, the role of quantum fields and renormalization and the
alleged impossibility of action-at-a-distance. A new perspective on these
issues is suggested. It can help to solve the old problem of theoretical
physics -- a consistent unification of relativity and quantum mechanics.
Under the above title, D. Van Nostrand Company, Inc. will shortly publish the book from which the following article is excerpted. Dr. Southworth is one of the leading authorities on waveguides and was one of the first to foresee the great usefulness that this form of transmission might offer. The editors of the Hell System Technical Journal are grateful for permission to publish here parts of the preface and the historical introduction and chapter 6 in its entirety.
Phase, group, and signal velocity are defined. Simple examples are given in which the phase and group velocities exceed the velocity of light, in which the phase velocity is a function of distance, and in which the group velocity is equal to the signal velocity.
Scitation is the online home of leading journals and conference proceedings from AIP Publishing and AIP Member Societies
Scitation is the online home of leading journals and conference proceedings from AIP Publishing and AIP Member Societies
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