In this paper, a penetrating analysis is first made of the superluminal and negative group velocities that occur in the EM wave propagation. Discussed then are the superluminal and negative group velocities which are ...In this paper, a penetrating analysis is first made of the superluminal and negative group velocities that occur in the EM wave propagation. Discussed then are the superluminal and negative group velocities which are in the state of evanescent waves in the waveguide below cutoff(WBCO).Through an experiment in the coaxial photonic crystal a group velocity of 1.5-2.4 times the speed of light are observed in the stop band.展开更多
We investigate the controllable group velocity of a microwave probe field in a superconductive quantum circuit（SQC） pumped by microwave fields,and the use of such a SQC function as an artificial Λ-type three-level ...We investigate the controllable group velocity of a microwave probe field in a superconductive quantum circuit（SQC） pumped by microwave fields,and the use of such a SQC function as an artificial Λ-type three-level atom.The exchange between the subluminal and the superluminal states of the probe field can be realized simply by sweeping the pumping intensity,and the superluminal state is usually realized with a lower absorption.This work is one of the efforts to extend the study of electromagnetically induced transparency and its related properties from the lightwave band to the microwave band.展开更多
Richard Feynman once said, “I think it is safe to say that no one understands Quantum Mechanics”. The well-known article on the Einstein-Podolsky-Rosen (EPR) paradox brought forth further doubts on the interpretatio...Richard Feynman once said, “I think it is safe to say that no one understands Quantum Mechanics”. The well-known article on the Einstein-Podolsky-Rosen (EPR) paradox brought forth further doubts on the interpretation of quantum theory. Einstein’s doubt on quantum theory is a doubleedged sword: experimental verification of quantum theory would contradict the hypothesis that speed of light is finite. It has been almost a century since the creation of quantum theory and special relativity, and the relevant doubts brought forward remain unresolved. We posit that the existence of discontinuity points and quantum wormholes would imply superluminal phenomenon or infinite speed of light, which provides for an important supplement to the invariance principle of the speed of light and superluminal phenomena. This can potentially resolve the inconsistency between special relativity and quantum theory.展开更多
A relativistic beaming model has been successfully used to explain the observed properties of active galactic nuclei (AGNs). In this model there are two emission components, a boosted one and an unbeamed one, shown up...A relativistic beaming model has been successfully used to explain the observed properties of active galactic nuclei (AGNs). In this model there are two emission components, a boosted one and an unbeamed one, shown up in the radio band as the core and lobe components. The luminosity ratio of the core to the lobe is defined as the core-dominance parameter (R = (L<SUB>Core</SUB>/L<SUB>Lobe</SUB>)). The de-beamed radio luminosity (L<SUB>jet</SUB><SUP>db</SUP>) in the jet is assumed to be proportional to the unbeamed luminosity (L<SUB>ub</SUB>) in the co-moving frame, i.e., f = (L<SUB>jet</SUB><SUP>db</SUP>/L<SUB>ub</SUB>), and f is determined in our previous paper. We further discuss the relationship between BL Lacertae objects (BLs) and flat spectrum radio quasars (FSRQs), which are subclasses of blazars with different degrees of polarization, using the calculated values of the ratio f for a sample of superluminal blazars. We found 1) that the BLs show smaller averaged Doppler factors and Lorentz factors, larger viewing angles and higher core-dominance parameters than do the FSRQs, and 2) that in the polarization-core dominance parameter plot (P-log R) the BLs and FSRQs occupy a scattered region, but in a revised plot (log (P/c(m)) ? log R), they gather around two different lines, suggesting that they have some different intrinsic properties.展开更多
The propagation of narrow packets of electromagnetic waves（EMWs） in frequency dispersive medium with the consideration of the complex refractive index is studied. It is shown that counting in the dispersion of the c...The propagation of narrow packets of electromagnetic waves（EMWs） in frequency dispersive medium with the consideration of the complex refractive index is studied. It is shown that counting in the dispersion of the complex refractive index within the context of the conventional expression of the group velocity of narrow wave packets of EMWs propagating in a dispersive medium results in the appearance of additional constraints on the group velocity, which dictates that the physically acceptable group velocity can only be realized in the case of a negligible imaginary part of the group index. In this paper, the conditions that allow one to realize the physically acceptable group velocity are formulated and analyzed numerically for the relevant model of the refractive index of a system of two-level atoms in the optical frequency range. It is shown that in the frequency band where superluminal light propagation is expected, there is a strong dispersion of the refractive index that is accompanied with strong absorption, resulting in a strongly attenuated superluminal light.展开更多
We study the light propagation properties in a V-type three-level atomic system interacting with two independent broadband squeezed baths. Using the graphic method, the dependences of the absorption and the dispersion...We study the light propagation properties in a V-type three-level atomic system interacting with two independent broadband squeezed baths. Using the graphic method, the dependences of the absorption and the dispersion of the system on the coupling field strength, the incoherent pumping field strength and the intensity of the squeezed vacuum are analysed. The result shows that the probe pulse propagation can be changed from subluminal to superluminal speed.展开更多
We study the absorption-dispersion process and group index of weak probe field in a four-level Er^3＋：YAG crystal.We find that the Er^3＋ion concentration and incoherent pumping field can influence the absorption-dis...We study the absorption-dispersion process and group index of weak probe field in a four-level Er^3＋：YAG crystal.We find that the Er^3＋ion concentration and incoherent pumping field can influence the absorption-dispersion process and group index of weak probe field. Moreover, our results show that Er^3＋ion concentration plays a major role in lasing without inversion and absorption with inversion.展开更多
In this article, a novel speculative method is used to derive the relativistic mechanic that governs the motion of the vibrating string within the compactified-dimensions spacetime. This mechanic claims that the relat...In this article, a novel speculative method is used to derive the relativistic mechanic that governs the motion of the vibrating string within the compactified-dimensions spacetime. This mechanic claims that the relativistic mechanic of the special relativity should be only valid for the motion within the familiar four-dimensional spacetime. However, our novel mechanic is valid for the motion within the compactified-dimensions spacetime predicted by the string theory. The equations of this new mechanic show that the vibrating string can move within the compactified dimensions in a speed that is faster than light. It is also shown that this new relativistic mechanic goes to the classical Newtonian mechanic whenever the speed of the vibrating string is much less than the speed of light. Since the proposed mechanic does not prohibit the existence faster than light motion, it may uncover some of the mysteries regarding the string theory, such as the existence of tachyon and time travel. The main goal of this paper is to show that the motion within the compactified-dimensions spacetime obeys a different relativistic mechanic that will provide a startling and revolutionary perspective on the universe and answer some of the fundamental questions posed in the modern physics.展开更多
Unlike the luminous objects observed, dark matter does not emit light but can be only detected by its gravitational effect. Modern cosmology considers that most matter in Universe is dark matter. However, it is still ...Unlike the luminous objects observed, dark matter does not emit light but can be only detected by its gravitational effect. Modern cosmology considers that most matter in Universe is dark matter. However, it is still not clear what the dark matter was. Two origins have been proposed by astrophysicists, astrophysics candidates and particle physics candidates. The most differences are their morphology, the former are compact objects and the latter are dispersed. Under Einstein</span><span style="font-family:Verdana;">’</span><span style="font-family:""><span style="font-family:Verdana;">s theory of general relativity, light bends as it passes near a compact object, creating a convergence effect like a lens. When background light source, intervening lense and the observer lie on a straight line, the brightness of the background source will be significantly magnified. In astrophysics, this effect is called microlensing. If compact dark matter is abundant in the universe, it is possible to frequently observe “microlensing” events when observing high redshift objects, </span><i><span style="font-family:Verdana;">i.e.</span></i><span style="font-family:Verdana;"> the objects temporarily brighten for a certain time. The microlensing technique has been applied to study the dark matter in halo of Milky Way. The difficulty occurs when applying to study the cosmic dark matter as the crossing time of cosmic microlensing events </span></span><span style="font-family:Verdana;">is</span><span style="font-family:Verdana;"> too long for observations. Apparent superluminal jets in bright quasars are idea background objects, significantly enhancing the efficiency of cosmic microlensing survey. Here, we tentatively designed an observational experiment to study the morphology of dark matter in Universe via statistics of microlensing events towards luminous quasars with apparent superluminal jets.展开更多
We investigate the influence of Doppler broadening on absorption-dispersion properties in a four-level atomic system that can evolve from a normal dispersion to an anomalous dispersion. Our results show that the absor...We investigate the influence of Doppler broadening on absorption-dispersion properties in a four-level atomic system that can evolve from a normal dispersion to an anomalous dispersion. Our results show that the absorption-dispersion properties become strongly dependent on the propagation directions of the applied fields if Doppler broadening is taken into account. Especially, the switchover in the sign of the dispersion is still achievable even in the presence of Doppler broadening if properly arranging the propagation directions of the applied fields, which is in contrast with the otherwise behaviours in some other configurations.展开更多
In this work we continue to set up the theory of universal space and time and derive the Euclidean form of the scaling transformations. Two types of velocities emerge, inertial and universal, with the former bound by ...In this work we continue to set up the theory of universal space and time and derive the Euclidean form of the scaling transformations. Two types of velocities emerge, inertial and universal, with the former bound by the light velocity c whereas the latter is unbound, and may accommodate consistently particles’ velocities possibly exceeding c. The inertial velocity is the ratio of the simultaneous source’s displacement and the corresponding length of the light trip to the observer, whereas the universal velocity has its familiar meaning for motion in a synchronous inertial frame. Defining the momentum as the product of universal velocity and mass, and utilizing the already established mass-energy equivalence, the mechanics constructed on the bases of the new concepts, named universal mechanics, admits superluminal velocities but yet coincides with the relativistic mechanics in its basic dynamical components and their inter-relations. The possibility of superluminal velocities provides a straight forward explanation of the presence of the μ-meson particles abundantly at the sea level despite their generation at high altitude and their short lifetime.展开更多
Entanglement and the tunnel effect phenomena have been repeatedly observed and are generically accepted under orthodox quantum mechanics formalism. However, they remain rather inexplicable in the context of spacetime ...Entanglement and the tunnel effect phenomena have been repeatedly observed and are generically accepted under orthodox quantum mechanics formalism. However, they remain rather inexplicable in the context of spacetime usual conceptualization. In the present work, we suggest an alternative quantum mechanics formalism, refining the pilot-wave theory initially proposed by de Broglie. We suggest that spacetime is an emergent phenomenon from a prior subquantum medium and that entanglement and the tunnel effect can be explained in terms of a nonlinear relation between space and time that is imposed by subquantum waves.展开更多
文摘In this paper, a penetrating analysis is first made of the superluminal and negative group velocities that occur in the EM wave propagation. Discussed then are the superluminal and negative group velocities which are in the state of evanescent waves in the waveguide below cutoff(WBCO).Through an experiment in the coaxial photonic crystal a group velocity of 1.5-2.4 times the speed of light are observed in the stop band.
基金Project supported by the National Natural Science Foundation of China (Grant No. 111174040)the Fundamental Research Funds for the Central Universities
文摘We investigate the controllable group velocity of a microwave probe field in a superconductive quantum circuit（SQC） pumped by microwave fields,and the use of such a SQC function as an artificial Λ-type three-level atom.The exchange between the subluminal and the superluminal states of the probe field can be realized simply by sweeping the pumping intensity,and the superluminal state is usually realized with a lower absorption.This work is one of the efforts to extend the study of electromagnetically induced transparency and its related properties from the lightwave band to the microwave band.
文摘Richard Feynman once said, “I think it is safe to say that no one understands Quantum Mechanics”. The well-known article on the Einstein-Podolsky-Rosen (EPR) paradox brought forth further doubts on the interpretation of quantum theory. Einstein’s doubt on quantum theory is a doubleedged sword: experimental verification of quantum theory would contradict the hypothesis that speed of light is finite. It has been almost a century since the creation of quantum theory and special relativity, and the relevant doubts brought forward remain unresolved. We posit that the existence of discontinuity points and quantum wormholes would imply superluminal phenomenon or infinite speed of light, which provides for an important supplement to the invariance principle of the speed of light and superluminal phenomena. This can potentially resolve the inconsistency between special relativity and quantum theory.
基金This work is partially supported by the National 973 projectthe National Science Fundfor Distinguished Young Scholars.
文摘A relativistic beaming model has been successfully used to explain the observed properties of active galactic nuclei (AGNs). In this model there are two emission components, a boosted one and an unbeamed one, shown up in the radio band as the core and lobe components. The luminosity ratio of the core to the lobe is defined as the core-dominance parameter (R = (L<SUB>Core</SUB>/L<SUB>Lobe</SUB>)). The de-beamed radio luminosity (L<SUB>jet</SUB><SUP>db</SUP>) in the jet is assumed to be proportional to the unbeamed luminosity (L<SUB>ub</SUB>) in the co-moving frame, i.e., f = (L<SUB>jet</SUB><SUP>db</SUP>/L<SUB>ub</SUB>), and f is determined in our previous paper. We further discuss the relationship between BL Lacertae objects (BLs) and flat spectrum radio quasars (FSRQs), which are subclasses of blazars with different degrees of polarization, using the calculated values of the ratio f for a sample of superluminal blazars. We found 1) that the BLs show smaller averaged Doppler factors and Lorentz factors, larger viewing angles and higher core-dominance parameters than do the FSRQs, and 2) that in the polarization-core dominance parameter plot (P-log R) the BLs and FSRQs occupy a scattered region, but in a revised plot (log (P/c(m)) ? log R), they gather around two different lines, suggesting that they have some different intrinsic properties.
文摘The propagation of narrow packets of electromagnetic waves（EMWs） in frequency dispersive medium with the consideration of the complex refractive index is studied. It is shown that counting in the dispersion of the complex refractive index within the context of the conventional expression of the group velocity of narrow wave packets of EMWs propagating in a dispersive medium results in the appearance of additional constraints on the group velocity, which dictates that the physically acceptable group velocity can only be realized in the case of a negligible imaginary part of the group index. In this paper, the conditions that allow one to realize the physically acceptable group velocity are formulated and analyzed numerically for the relevant model of the refractive index of a system of two-level atoms in the optical frequency range. It is shown that in the frequency band where superluminal light propagation is expected, there is a strong dispersion of the refractive index that is accompanied with strong absorption, resulting in a strongly attenuated superluminal light.
基金supported by the National Natural Science Foundation of China (Grant No.10874138)
文摘We study the light propagation properties in a V-type three-level atomic system interacting with two independent broadband squeezed baths. Using the graphic method, the dependences of the absorption and the dispersion of the system on the coupling field strength, the incoherent pumping field strength and the intensity of the squeezed vacuum are analysed. The result shows that the probe pulse propagation can be changed from subluminal to superluminal speed.
文摘We study the absorption-dispersion process and group index of weak probe field in a four-level Er^3＋：YAG crystal.We find that the Er^3＋ion concentration and incoherent pumping field can influence the absorption-dispersion process and group index of weak probe field. Moreover, our results show that Er^3＋ion concentration plays a major role in lasing without inversion and absorption with inversion.
文摘In this article, a novel speculative method is used to derive the relativistic mechanic that governs the motion of the vibrating string within the compactified-dimensions spacetime. This mechanic claims that the relativistic mechanic of the special relativity should be only valid for the motion within the familiar four-dimensional spacetime. However, our novel mechanic is valid for the motion within the compactified-dimensions spacetime predicted by the string theory. The equations of this new mechanic show that the vibrating string can move within the compactified dimensions in a speed that is faster than light. It is also shown that this new relativistic mechanic goes to the classical Newtonian mechanic whenever the speed of the vibrating string is much less than the speed of light. Since the proposed mechanic does not prohibit the existence faster than light motion, it may uncover some of the mysteries regarding the string theory, such as the existence of tachyon and time travel. The main goal of this paper is to show that the motion within the compactified-dimensions spacetime obeys a different relativistic mechanic that will provide a startling and revolutionary perspective on the universe and answer some of the fundamental questions posed in the modern physics.
文摘Unlike the luminous objects observed, dark matter does not emit light but can be only detected by its gravitational effect. Modern cosmology considers that most matter in Universe is dark matter. However, it is still not clear what the dark matter was. Two origins have been proposed by astrophysicists, astrophysics candidates and particle physics candidates. The most differences are their morphology, the former are compact objects and the latter are dispersed. Under Einstein</span><span style="font-family:Verdana;">’</span><span style="font-family:""><span style="font-family:Verdana;">s theory of general relativity, light bends as it passes near a compact object, creating a convergence effect like a lens. When background light source, intervening lense and the observer lie on a straight line, the brightness of the background source will be significantly magnified. In astrophysics, this effect is called microlensing. If compact dark matter is abundant in the universe, it is possible to frequently observe “microlensing” events when observing high redshift objects, </span><i><span style="font-family:Verdana;">i.e.</span></i><span style="font-family:Verdana;"> the objects temporarily brighten for a certain time. The microlensing technique has been applied to study the dark matter in halo of Milky Way. The difficulty occurs when applying to study the cosmic dark matter as the crossing time of cosmic microlensing events </span></span><span style="font-family:Verdana;">is</span><span style="font-family:Verdana;"> too long for observations. Apparent superluminal jets in bright quasars are idea background objects, significantly enhancing the efficiency of cosmic microlensing survey. Here, we tentatively designed an observational experiment to study the morphology of dark matter in Universe via statistics of microlensing events towards luminous quasars with apparent superluminal jets.
文摘We investigate the influence of Doppler broadening on absorption-dispersion properties in a four-level atomic system that can evolve from a normal dispersion to an anomalous dispersion. Our results show that the absorption-dispersion properties become strongly dependent on the propagation directions of the applied fields if Doppler broadening is taken into account. Especially, the switchover in the sign of the dispersion is still achievable even in the presence of Doppler broadening if properly arranging the propagation directions of the applied fields, which is in contrast with the otherwise behaviours in some other configurations.
文摘In this work we continue to set up the theory of universal space and time and derive the Euclidean form of the scaling transformations. Two types of velocities emerge, inertial and universal, with the former bound by the light velocity c whereas the latter is unbound, and may accommodate consistently particles’ velocities possibly exceeding c. The inertial velocity is the ratio of the simultaneous source’s displacement and the corresponding length of the light trip to the observer, whereas the universal velocity has its familiar meaning for motion in a synchronous inertial frame. Defining the momentum as the product of universal velocity and mass, and utilizing the already established mass-energy equivalence, the mechanics constructed on the bases of the new concepts, named universal mechanics, admits superluminal velocities but yet coincides with the relativistic mechanics in its basic dynamical components and their inter-relations. The possibility of superluminal velocities provides a straight forward explanation of the presence of the μ-meson particles abundantly at the sea level despite their generation at high altitude and their short lifetime.
文摘Entanglement and the tunnel effect phenomena have been repeatedly observed and are generically accepted under orthodox quantum mechanics formalism. However, they remain rather inexplicable in the context of spacetime usual conceptualization. In the present work, we suggest an alternative quantum mechanics formalism, refining the pilot-wave theory initially proposed by de Broglie. We suggest that spacetime is an emergent phenomenon from a prior subquantum medium and that entanglement and the tunnel effect can be explained in terms of a nonlinear relation between space and time that is imposed by subquantum waves.
