We propose an exactly solvable method to study the coherent two-colour photoassociation of an atomic Bose- Einstein condensate, by linearizing the bilinear atom-molecule coupling, which allows us to conveniently probe...We propose an exactly solvable method to study the coherent two-colour photoassociation of an atomic Bose- Einstein condensate, by linearizing the bilinear atom-molecule coupling, which allows us to conveniently probe the quantum dynamics and statistics of the system. By preparing different initial states of the atomic condensate, we can observe very different quantum statistical properties of the system by exactly calculating the quadrature- squeezed and mode-correlated functions.展开更多
From Jan.1991 to Dec.1995,we treatedwith TCM nearly one thousand confirmedHIV/AIDS patients in Muhimbili MedicalCenter,Tanzania.Of them,437 cases withcomplete data have been summarized
In the centenary year of Einstein's General Theory of Relativity, this paper reviews the current status of gravitational wave astronomy across a spectrum which stretches from attohertz to kilohertz frequencies. Se...In the centenary year of Einstein's General Theory of Relativity, this paper reviews the current status of gravitational wave astronomy across a spectrum which stretches from attohertz to kilohertz frequencies. Sect. 1 of this paper reviews the historical development of gravitational wave astronomy from Einstein's first prediction to our current understanding the spectrum. It is shown that detection of signals in the audio frequency spectrum can be expected very soon, and that a north-south pair of next generation detectors would provide large scientific benefits. Sect. 2 reviews the theory of gravitational waves and the principles of detection using laser interferometry. The state of the art Advanced LIGO detectors are then described. These detectors have a high chance of detecting the first events in the near future. Sect. 3 reviews the KAGRA detector currently under development in Japan,which will be the first laser interferometer detector to use cryogenic test masses. Sect. 4 of this paper reviews gravitational wave detection in the nanohertz frequency band using the technique of pulsar timing. Sect. 5 reviews the status of gravitational wave detection in the attohertz frequency band, detectable in the polarisation of the cosmic microwave background, and discusses the prospects for detection of primordial waves from the big bang. The techniques described in sects. 1–5 have already placed significant limits on the strength of gravitational wave sources. Sects. 6 and 7 review ambitious plans for future space based gravitational wave detectors in the millihertz frequency band. Sect. 6 presents a roadmap for development of space based gravitational wave detectors by China while sect. 7 discusses a key enabling technology for space interferometry known as time delay interferometry.展开更多
With the dark energy phenomena explored over a decade, in this present work we discuss a specific case of the generalized Einstein-aether theories, in which the modified Friedmann equation is similar to that in the Dv...With the dark energy phenomena explored over a decade, in this present work we discuss a specific case of the generalized Einstein-aether theories, in which the modified Friedmann equation is similar to that in the Dvali- Gabadadze-Porrati （DGP） brahe world model. We compute the joint statistic constraints on model parameters in this specific case by using the recent type Ia supernovae （SNe Ia） data, the cosmic microwave background （CMB） shift parameter data, and the baryonic acoustic oscillations （BAOs） data traced by the S1oan Digital Sky Survey （SDSS）. Furthermore, we analyze other constrains from the observational Hubble parameter data （OHD）. The comparison with the standard cosmological model （cosmological constant A cold dark matter （ACDM） model） is dearly shown; also we comment on the interesting relation between the coupling constant M in this model and the special accelerate scale in the modified Newtonian dynamies （MOND） model initially given by Milgrom with the hope for interpreting the galaxy rotation curves without introducing mysterious dark matter.展开更多
基金Supported by the National Basic Research Program of China under Grant No 2007CB307002, the National Natural Science Foundation of China under Grant Nos 10334010 and 10304020, the PCSIRT, the 111 Project （B07013）, Key International ST Cooperation Project under Grant No 2005DFA10170, the Cultivation Fund of the Key Scientific and Technical Innovation Project, the Ministry of Education of China under Grant No 704012, and the Wuhan Youth Chen-Guang Programme.
文摘We propose an exactly solvable method to study the coherent two-colour photoassociation of an atomic Bose- Einstein condensate, by linearizing the bilinear atom-molecule coupling, which allows us to conveniently probe the quantum dynamics and statistics of the system. By preparing different initial states of the atomic condensate, we can observe very different quantum statistical properties of the system by exactly calculating the quadrature- squeezed and mode-correlated functions.
文摘From Jan.1991 to Dec.1995,we treatedwith TCM nearly one thousand confirmedHIV/AIDS patients in Muhimbili MedicalCenter,Tanzania.Of them,437 cases withcomplete data have been summarized
基金supported by the US National Science Foundation(Grant No.PHY-0757058)supported by the National Natural Science Foundation of China(Grant Nos.11443008 and 11503003)+2 种基金a Returned Overseas Chinese Scholars Foundation grant,and Fundamental Research Funds for the Central Universities(Grant No.2015KJJCB06)supported by the National Space Science Center,Chinese Academy of Sciences(Grant Nos.XDA04070400 and XDA04077700)Partial supports from the National Natural Science Foundation of China(Grant Nos.11305255,11171329 and 41404019)
文摘In the centenary year of Einstein's General Theory of Relativity, this paper reviews the current status of gravitational wave astronomy across a spectrum which stretches from attohertz to kilohertz frequencies. Sect. 1 of this paper reviews the historical development of gravitational wave astronomy from Einstein's first prediction to our current understanding the spectrum. It is shown that detection of signals in the audio frequency spectrum can be expected very soon, and that a north-south pair of next generation detectors would provide large scientific benefits. Sect. 2 reviews the theory of gravitational waves and the principles of detection using laser interferometry. The state of the art Advanced LIGO detectors are then described. These detectors have a high chance of detecting the first events in the near future. Sect. 3 reviews the KAGRA detector currently under development in Japan,which will be the first laser interferometer detector to use cryogenic test masses. Sect. 4 of this paper reviews gravitational wave detection in the nanohertz frequency band using the technique of pulsar timing. Sect. 5 reviews the status of gravitational wave detection in the attohertz frequency band, detectable in the polarisation of the cosmic microwave background, and discusses the prospects for detection of primordial waves from the big bang. The techniques described in sects. 1–5 have already placed significant limits on the strength of gravitational wave sources. Sects. 6 and 7 review ambitious plans for future space based gravitational wave detectors in the millihertz frequency band. Sect. 6 presents a roadmap for development of space based gravitational wave detectors by China while sect. 7 discusses a key enabling technology for space interferometry known as time delay interferometry.
基金Supported by Natural Science Foundation of China under Grant Nos. 11075078 and 10675062by the project of knowledge Innovation Program (PKIP) of Chinese Academy of Sciences (CAS) under Grant No. KJCX2.YW.W10 through the KITPC astrophysics and cosmology programmes where we have initiated this present work
文摘With the dark energy phenomena explored over a decade, in this present work we discuss a specific case of the generalized Einstein-aether theories, in which the modified Friedmann equation is similar to that in the Dvali- Gabadadze-Porrati （DGP） brahe world model. We compute the joint statistic constraints on model parameters in this specific case by using the recent type Ia supernovae （SNe Ia） data, the cosmic microwave background （CMB） shift parameter data, and the baryonic acoustic oscillations （BAOs） data traced by the S1oan Digital Sky Survey （SDSS）. Furthermore, we analyze other constrains from the observational Hubble parameter data （OHD）. The comparison with the standard cosmological model （cosmological constant A cold dark matter （ACDM） model） is dearly shown; also we comment on the interesting relation between the coupling constant M in this model and the special accelerate scale in the modified Newtonian dynamies （MOND） model initially given by Milgrom with the hope for interpreting the galaxy rotation curves without introducing mysterious dark matter.
