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1.
理论估计传到地球上的引力波非常弱,激光干涉引力波探测器被设计用来探测引力波,在没有引力波传来时,激光干涉引力波探测器应该是零输出。为达到这样的目的,必须和众多的噪声作斗争。 相似文献
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3.
Dennis Lorek Andreas Wicht Claus Lämmerzahl 《General Relativity and Gravitation》2011,43(7):2053-2064
We present an orientational quantum interferometer sensitive to gravitational waves that is based on orienting quantum objects
like molecules, atoms, or nuclei in space. The detection principle is based on inducing non-sphericity to the corresponding
wave functions by light-pulses. In the field of a gravitational wave these objects then possess spectra that depend on their
orientation in space. In our measurement scheme we investigate the adiabatic influence of a monochromatic gravitational wave
over a quarter gravitational wave period and compare the corresponding frequencies at instances with maximal and vanishing
gravitational wave elongation. We therefore explore the effect over a quarter gravitational wave period (or wavelength) and
the resulting frequency shift scales with the binding energy of the system times the amplitude of the gravitational wave.
In particular, a gravitational wave with amplitude h = 10−23 will induce a frequency shift of the order of 110 μHz for an atom interferometer based on a 91-fold charged uranium ion. 相似文献
4.
By making use of the weak gravitational field approximation, we obtain a linearized solution of the gravitational vacuum field equation in an anisotropic spacetime. The plane-wave solution and dispersion relation of gravitationaJ wave is presented explicitly. There is possibility that the speed of gravitational wave is larger than the speed of light and the easuality still holds. We show that the energy-momentum of gravitational wave in the ansiotropic spacetime is still well defined and conserved. 相似文献
5.
By making use of the weak gravitational field approximation, we obtain a linearized solution of the gravitational vacuum field equation in an anisotropic spacetime. The plane-wave solution and dispersion relation of gravitational wave is presented explicitly. There is possibility that the speed of gravitational wave is larger than the speed of light and the casuality still holds. We show that the energy-momentum of gravitational wave in the ansiotropic spacetime is still well defined and conserved. 相似文献
6.
引力波的直接观测已开启引力波天文学的新篇章,爱因斯坦的百年预言终获证实。空间引力波探测器使得探测0.1 m Hz~1 Hz频段丰富的引力波源成为可能,与地面引力波探测器互为补充,才可实现更加宽广波段的引力波探测,揭开宇宙早期的更多秘密。空间激光干涉引力波探测采用外差干涉测量技术,测量间距百万公里的两自由悬浮测试质量间10 pm量级的变化量。望远镜是激光干涉测量系统的重要组成部分,1 pm的光程稳定性及苛刻的杂散光要求,不同于传统的几何成像望远镜。本文根据空间太极计划任务需求,对望远镜的功能及技术要求进行了分析,并完成了原理样机的初步方案设计,针对百万公里远场波前分布,分析了望远镜系统的敏感性,同时完成了在轨光机热集成仿真,为后面原理样机的研制奠定了技术基础。 相似文献
7.
Adrian Kent 《Foundations of Physics》2013,43(6):707-718
A quantum measurement-like event can produce any of a number of macroscopically distinct results, with corresponding macroscopically distinct gravitational fields, from the same initial state. Hence the probabilistically evolving large-scale structure of space-time is not precisely or even always approximately described by the deterministic Einstein equations. Since the standard treatment of gravitational wave propagation assumes the validity of the Einstein equations, it is questionable whether we should expect all its predictions to be empirically verified. In particular, one might expect the stochasticity of amplified quantum indeterminacy to cause coherent gravitational wave signals to decay faster than standard predictions suggest. This need not imply that the radiated energy flux from gravitational wave sources differs from standard theoretical predictions. An underappreciated bonus of gravitational wave astronomy is that either detecting or failing to detect predicted gravitational wave signals would constrain the form of the semi-classical theory of gravity that we presently lack. 相似文献
8.
The first generation of gravitational wave interferometric detectors have taken data at, or close to, their design sensitivity.
This data has been searched for a broad range of gravitational wave signatures. An overview of gravitational wave search methods
and results are presented. Searches for gravitational waves from unmodelled burst sources, compact binary coalescences, continuous
wave sources and stochastic backgrounds are discussed. 相似文献
9.
Photon motion in a Michelson interferometer is re-analyzed in terms of both geometrical optics and wave optics.The classical paths of the photons in the background of a gravitational wave are derived from the Fermat principle,which is the same as the null geodesics in general relativity.The deformed Maxwell equations and the wave equations of electric fields in the background of a gravitational wave are presented in a flat-space approximation.Both methods show that even the envelope of the response of an interferometer depends on the frequency of a gravitational wave,but it is almost independent of the frequency of the mirror's vibrations. 相似文献
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A critical review of gravitational wave theory is made. It is pointed out that the usual linear approach to the gravitational
wave theory is neither conceptually consistent nor mathematically justified. Relying upon that analysis it is argued that—analogously
to a Yang-Mills propagating field, which must be nonlinear to carry its gauge charge—a gravitational wave must necessarily
be nonlinear to transport its own charge—that is, energy-momentum. 相似文献
11.
从弱引力场的Einstein-Maxwell方程出发,讨论了晶体空间阵列的狭窄波束型高频引力辐射与电磁场的作用效应,并给出了扰动解。计算表明,在TT(Transvese Traceless)坐标系中,最优辐射方向的引力波束是纯十型极化的,并可使同频的电磁波产生倍频的扰动效应,使静态电磁场产生与时间成线性关系的累积扰动效应。对于任意方向上的引力辐射波束,在垂直于引力波矢的平面内仍然是纯十型极化的。在高频辐射和实验室典型尺度条件下,TT坐标系与Fermi坐标系的差异是可以忽略的。
关键词: 相似文献
12.
Walter Velloso Fabrizio Barone Enrico Calloni Luciano Di Fiore Aniello Grado Leopoldo Milano Guido Russo 《General Relativity and Gravitation》1996,28(5):613-631
The main features of continuous gravitational radiation bathing the Earth has been evaluated for a set of 558 pulsars. In particular, the maximum gravitational wave background and the maximum gravitational wave emission have been evaluated for each source and compared with the projected sensitivities of the planned Earth based very long baseline interferometric antennas for gravitational wave detection, like VIRGO and LIGO. This study shows that such detectors have a good chance of detecting gravitational waves emitted from this class of astrophysical sources. 相似文献
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We have analyzed the exact behavior of the polarization vector of a linearly polarized electromagnetic shock wave upon crossing a gravitational sandwich wave, by using Einstein's theory of general relativity. The Faraday rotation in the polarization vector of the electromagnetic field is induced in this nonlinear process. We show that the Faraday's angle highly depends on the electromagnetic parameter, gravitational parameter and the width of the gravitational sandwich wave. 相似文献
14.
《中国物理快报》2016,(8)
A three-arm Michelson-Fabry-Perot detector for gravitational waves is designed.It consists of three MichelsonFabry-Perot interferometers,one for each pair of arms.The new detector can be used to confirm whether the gravitational waves are in general relativity polarization states and to set the strong constraints on non-GR gravitational wave polarization states.By the new detectors,the angular resolution of sources can be improved significantly.With the new detector,it is easier to search for and confirm a gravitational wave signal in the observation data. 相似文献
15.
We present a novel nonlinear mechanism for exciting a gravitational radiation pulse (or a gravitational wave) by dust magnetohydrodynamic (DMHD) waves in dusty astrophysical plasmas. We derive the relevant equations governing the dynamics of nonlinearly coupled DMHD waves and a gravitational wave (GW). The system of equations is used to investigate the generation of a GW by compressional Alfvén waves in a type II supernova. The growth rate of our nonlinear process is estimated, and the results are discussed in the context of the gravitational radiation accompanying supernova explosions. 相似文献
16.
Roman Tomaschitz 《International Journal of Theoretical Physics》1997,36(4):955-977
The propagation of linear gravitational waves is studied in open and multiply connected Robertson-Walker cosmologies. In order
for the group velocity of the gravitational wave packets to coincide with the speed of light, the linear wave equation must
be conformally coupled. This opens the possibility of using the electromagnetic formalism. The gravitational analogue to the
electromagnetic field tensor is introduced, and a tensorial counterpart to Maxwell's equations on the spacelike 3-slices is
derived. The energy-momentum tensor for linear gravitational waves is constructed without averaging procedures, a strictly
positive energy density is obtained, and it is shown that the overall energy of a gravitational pulse scales with the inverse
of the expansion factor. 相似文献
17.
《中国科学:物理学 力学 天文学(英文版)》2021,(5)
Models of the coupling of electromagnetic and gravitational fields have been studied extensively for many years. In this paper,we consider the coupling between the Maxwell field and the Weyl tensor of the gravitational field to study how the wavevector of the electromagnetic wave is affected by a plane gravitational wave. We find that the wavevector depends upon the frequency and direction of polarization of the electromagnetic waves, the parameter that couples the Maxwell field and the Weyl tensor, and the angle between the direction of propagation of the electromagnetic wave and the coordinate axis. The results show that this coupling model can be tested by the detection of high-frequency gravitational waves. 相似文献
18.
Along with the development of the interferometric gravitational wave detector, we enter into an epoch of the gravitational
wave astronomy, which will open a brand new window for astrophysics to observe our universe. However, the gravitational wave
detection is a typical weak signal detection, and this weak signal is buried in a strong instrument noise. To our knowledge,
almost all of the data analysis methods in gravitational wave detection at present are based on a matched filtering. So it
is desirable to take advantage of stochastic resonance methods. However, the all of the stochastic resonance methods are general
based on a Fourier transformation and fall short of the matched filtering as a usable technique. In this paper we relate the
stochastic resonance to the matched filtering. Our results show that the stochastic resonance can indeed be combined with
the matched filtering for both the periodic and the non-periodic input signal. This encouraging result will be the first step
to apply the stochastic resonance to the matched filtering in gravitational wave detection. Moreover, based on the matched
filtering, we firstly propose a novel measurement method for the stochastic resonance which is valid for both the periodic
and the non-periodic driven signal. 相似文献
19.
Allen ZA Astone P Baggio L Busby D Bassan M Blair DG Bonaldi M Bonifazi P Carelli P Cerdonio M Coccia E Conti L Cosmelli C Crivelli Visconti V D'Antonio S Fafone V Falferi P Fortini P Frasca S Hamilton WO Heng IS Ivanov EN Johnson WW Kingham M Locke CR Marini A 《Physical review letters》2000,85(24):5046-5050
We report the initial results from a search for bursts of gravitational radiation by a network of five cryogenic resonant detectors during 1997 and 1998. This is the first significant search with more than two detectors observing simultaneously. No gravitational wave burst was detected. The false alarm rate was lower than 1 per 10(4) yr when three or more detectors were operating simultaneously. The typical threshold was H approximately 4x10(-21) Hz-1 on the Fourier component at approximately 10(3) Hz of the gravitational wave strain amplitude. New upper limits for amplitude and rate of gravitational wave bursts have been set. 相似文献
20.
The observation of GW150914 gave a new independent measurement of the luminosity distance of a gravitational wave event. In this paper, we constrain the anisotropy of the Universe by using gravitational wave events.We simulate hundreds of events of binary neutron star merger that may be observed by the Einstein Telescope. Full simulation of the production process of gravitational wave data is employed. We find that 200 binary neutron star merging events with the redshift in (0,1) observed by the Einstein Telescope may constrain the anisotropy with an accuracy comparable to that from the Union2.1 supernovae. This result shows that gravitational waves can be a powerful tool for investigating cosmological anisotropy. 相似文献