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The Theory of Relativity on the Finsler Spacetime
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作者 Cao ShengLin (Department of Astronomy, Beijing Normal University, Beijing 100875, China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1995年第4期239-252,共14页
According to some local properties of Lorentz transformation, Einstein stated: 'Vetheitiss greater than that of light have no possibility of existence.' He neglected to point out the applicable range of the sp... According to some local properties of Lorentz transformation, Einstein stated: 'Vetheitiss greater than that of light have no possibility of existence.' He neglected to point out the applicable range of the special theory of relativity. In fact, it could only be applied to the subluminal-speeds. This paper shows that if ones think of the possibility of the existence of the superluminal-speeds and redescribe the special theory of relativity following Einstein's way, it could be supposed that the physical spacetime is a Finsler spacetime, characterized by the metric ds4=gijkldxidxidxkdxl. If so, a new spactime transformation could be found by invariant ds4 and the theory of relativity is discussed on this transformation it is possible that the Finsler spacetime F(x,y) may be endowed with a catastrophic nature. Based on the different properties between the ds2 and ds4, it is discussed that the flat spacetime will also have the catastrophic nature on the Finsler metric ds4. The spacetime transformations and the Physical quantities will suddenly change at the catastrophe set of the spacetime, the light cone. It will be supposed that only the dual velocity of the superluminal-speeds could be observed. If so, a particle with the superluminal-speed v> c could be regarded as its anti-particle with the dual velocity v1=c2/ v< c. On the other hand, it could be assumed that the horizon of the field of the general relativity is also a catastrophic set. If so, a particle with the superluminal-speeds could be projected near the horizon of these fields, and the particle will move on the sauce-like curves. It is very interesting that, in the Schwarzschild fields, the theoretical calculation for the sauce-like curves should be in agreement with tie data of the superluminal expansion of extragalactic radio sources observed year after year. (see Gao, 1992b).The ca- tastrophe of spacetime has some deep cosmological means. According to the some interested subjects in the Process of evolution of the universe the catastrophe nature of the Finsler spacetime and its cosmological impli= cations are discussed. It is shown that the nature of the universal evolution could be attributed to the geometric features of the Finsler spacetime. (see Cao, 1993) 展开更多
关键词 Theory of relativity Finsler spacetime Superluminal-speed Subluminal-speed Catastrophe theory Superluminal expansion extragalactic radio sources COSMOLOGY
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Cosmological Distances in Closed Model of the Universe
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作者 Fadel A. Bukhari 《International Journal of Astronomy and Astrophysics》 2013年第2期199-203,共5页
Four Cosmological distances were determined in the light of the closed cosmic model which was presented in a previous study. Each of these distances was obtained in terms of the redshift of an extragalactic object. It... Four Cosmological distances were determined in the light of the closed cosmic model which was presented in a previous study. Each of these distances was obtained in terms of the redshift of an extragalactic object. It is found that the luminosity distance of the extragalactic object in the closed cosmic model, the observed model and model are approximately the same up to z = 0.1535. However, the luminosity distance in the close cosmic model approximately agrees with its value in the observed model up to z = 0.6442. Estimations of the horizon distance of the universe, the total mass and the mass of matter within the horizon distance, the equivalent numbers of the Milky Way-like galaxies and the Coma-like clusters of galaxies to the mass of matter were computed in the closed cosmic model at the present time. 展开更多
关键词 extragalactic DISTANCES COSMOLOGY COSMIC Dynamics COSMOLOGICAL Parameter
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Cosmological Distances in Five General Cosmic Models
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作者 Fadel A. Bukhari 《International Journal of Astronomy and Astrophysics》 2013年第2期183-188,共6页
Four cosmological distances were investigated in the light of the five general cosmic models which were developed in a previous study. These are the proper distance, luminosity distance, angular diameter distance and ... Four cosmological distances were investigated in the light of the five general cosmic models which were developed in a previous study. These are the proper distance, luminosity distance, angular diameter distance and distance modulus. Each of these distances was studied in terms of the redshift of the extragalactic objects. Estimations of the horizon distance of the universe, the total mass and the mass of matter within the horizon distance, the equivalent numbers of the Milky Way-like galaxies and the Coma-like clusters of galaxies to the mass of matter were determined in the general models at the present time. 展开更多
关键词 extragalactic DISTANCES COSMOLOGY COSMIC Dynamics
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The Giant Radio Array for Neutrino Detection(GRAND):Science and design 被引量:2
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作者 Jaime Alvarez-Muniz Rafael Alves Batista +47 位作者 Aswathi Balagopal V. Julien Bolmont Mauricio Bustamante Washington Carvalho Jr. Didier Charrier Ismael Cognard Valentin Decoene Peter B.Denton Sijbrand De Jong Krijn D.De Vries Ralph Engel Ke Fang Chad Finley Stefano Gabici Quan Bu Gou Jun Hua Gu Claire Guépin Hong Bo Hu Yan Huang Kumiko Kotera Sandra Le Coz Jean-Philippe Lenain Guo Liang Léü Olivier Martineau-Huynh Miguel Mostafá Fabrice Mottez Kohta Murase Valentin Niess Foteini Oikonomou Tanguy Pierog Xiang Li Qian Bo Qin Duan Ran Nicolas Renault-Tinacci Markus Roth Frank G.Schroder Fabian Schüssler Cyril Tasse Charles Timmerman Matías Tueros Xiang Ping Wu Philippe Zarka Andreas Zech B.Theodore Zhang Jian Li Zhang Yi Zhang Qian Zheng Anne Zilles 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2020年第1期1-43,共43页
The Giant Radio Array for Neutrino Detection(GRAND)is a planned large-scale observatory of ultra-high-energy(UHE)cosmic particles,with energies exceeding 10~8 Ge V.Its goal is to solve the long-standing mystery of the... The Giant Radio Array for Neutrino Detection(GRAND)is a planned large-scale observatory of ultra-high-energy(UHE)cosmic particles,with energies exceeding 10~8 Ge V.Its goal is to solve the long-standing mystery of the origin of UHE cosmic rays.To do this,GRAND will detect an unprecedented number of UHE cosmic rays and search for the undiscovered UHE neutrinos and gamma rays associated to them with unmatched sensitivity.GRAND will use large arrays of antennas to detect the radio emission coming from extensive air showers initiated by UHE particles in the atmosphere.Its design is modular:20 separate,independent sub-arrays,each of 10000 radio antennas deployed over 10000 km^2.A staged construction plan will validate key detection techniques while achieving important science goals early.Here we present the science goals,detection strategy,preliminary design,performance goals,and construction plans for GRAND. 展开更多
关键词 radio telescopes neutrinos in astronomical observations cosmic rays in astronomical observations radiowave radiation:sources galactic and extragalactic cosmic rays:galactic and extragalactic
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DUAL RELATIVISTIC EFFECTS IN RADIO JETS OF ACTIVE GALACTIC NUCLEI
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作者 钱善瑎 《Chinese Science Bulletin》 SCIE EI CAS 1988年第13期1097-1101,共5页
The apparent superluminal motions observed in some compact radio sources are an important astrophysical phenomenon. Recent VLBI (Very Long Baseline Interfer- ometer) observations have found that a new knot C4 which wa... The apparent superluminal motions observed in some compact radio sources are an important astrophysical phenomenon. Recent VLBI (Very Long Baseline Interfer- ometer) observations have found that a new knot C4 which was just ejected from the nucleus of the superluminal source 3C345 was both moving and expanding su- perluminally. So this is an apparent dual-superluminal phenomenon. If such a phe- 展开更多
关键词 extragalactic RADIO SOURCES SUPERLUMINAL MOTION RELATIVISTIC effect
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Implications of axion-like particles from the Fermi-LAT and H.E.S.S.observations of PG 1553+113 and PKS 2155−304
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作者 郭俊广 李海军 +2 位作者 毕效军 林苏杰 殷鹏飞 《Chinese Physics C》 SCIE CAS CSCD 2021年第2期578-587,共10页
We investigate the axion-like particle(ALP)-photon oscillation effect in the high-energy y-ray spectra of PG 1553+113 and PK.S 2155-304 measured by Fermi-LAT and H.E.S.S.The choice of extragalactic background light(EB... We investigate the axion-like particle(ALP)-photon oscillation effect in the high-energy y-ray spectra of PG 1553+113 and PK.S 2155-304 measured by Fermi-LAT and H.E.S.S.The choice of extragalactic background light(EBL)model,which induces the attenuation effect in observed y-ray spectra,affects the ALP implications.For the ordinary EBL model that prefers a null hypothesis,we set constraints on the ALP-photon coupling constant at 95% C.L.as gay 5×10^(-11) GeV^(-1) for the ALP mass 〜10 neV.We also consider the CIBER observation of the cosmic infrared radiation,which shows an excess at wavelengths of -1μm after the substraction of foregrounds.High-energy gamma-rays from extragalactic sources at high redshifts would suffer from a more significant attenuation effect caused by this excess.In this case,we find that the ALP-photon oscillation would improve the fit to the observed spectra of PKS 2155-304 and PG 1553+113 and find a favored parameter region at 95%CL.. 展开更多
关键词 axion-like particle GAMMA-RAY extragalactic background light
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