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1.
桂元星 《中国科学A辑》1988,31(3):282-290
本文在热场动力学和弯曲时空量子场论的基础上,提出了热量子场论。热量子场论完全从量子力学出发推出了平衡态统计的主要结果,而无须利用任何统计假设,并预言可能存在一种新的热平衡态——超热态,讨论了超热态的热力学性质。  相似文献   
2.
We evaluate the quasinormal modes of massless Dirac perturbation in a Schwarzschild black hole surrounded by the free static spherically symmetric quintessence using the third-order Wentzel-Kramers-Brillouin (WKB) approximation. The result shows that the massless Dirac field damps more slowly due to the presence of quintessence. The real part of the quasinormal modes increases and the absolute value of the imaginary part increases when the state parameter wq increases. In other words, the massless Dirac field decays more rapidly for the larger Wq. The peak value of potential barrier becomes higher as |k| increases and the location of peak moves along the right for fixed wq.  相似文献   
3.
桂元星 《中国科学A辑》1992,35(10):1079-1088
本文讨论了η-ξ时空与几种有限温度场论方法之间的联系.  相似文献   
4.
We consider a generalized quintom (GQ) dark energy model for changing the equal weight of the negative-kinetic scalar field (phantom) and the normal scalar field (quintessence) in quintom dark energy. Though the phantomdominated scaling solution is a stable late-time attractor, the early evolution of GQ is different from that of the quintom model and the adjustability of the dark energy state equation in the model is improved.  相似文献   
5.
In the framework of a five-dimensional (5D) bounce cosmological model, a useful function f(z) is obtained by giving a concrete expression of deceleration parameter q(z)=q1+{q2}/{1+ln (1+ z)}. Then using the obtained Hubble parameter H(z) according to the function f(z), we constrain the accelerating universe from recent cosmic observations: the 192 ESSENCE SNe Ia and the 9 observational H(z) data. The best fitting values of transition redshift zT and current deceleration parameter q0 are given as zT= 0.65-0.120.25 and q0 = - 0.76-0.15+0.15 (1σ). Furthermore, in the 5D bounce model it can be seen that the evolution of equation of state (EOS) for dark energy wde can cross over -1 at about z=0.23 and the current value w0de= - 1.15<- 1. On the other hand, by giving a concrete expression of model-independent EOS of dark energy wde, in the 5D bounce model we obtain the best fitting values zT= 0.660.08+0.11 and q0 = - 0.690.10+0.10 (1σ) from the recently observed data: the 192 ESSENCE SNe Ia, the observational H(z) data, the 3-year Wilkinson Microwave Anisotropy Probe (WMAP), the Sloan Digital Sky Survey (SDSS) baryon acoustic peak and the x-ray gas mass fraction in clusters.  相似文献   
6.
高亚军  桂元星 《物理学报》2000,49(3):415-420
将ηξ时空理论与适当的复时间变换有机结合,构造了所谓ηξ复时变换,它给出ηξ时空中的截面转动,从而诱导出虚时、实时热场理论间的直接变换,这从背景时空的角度揭示了虚时、实时热场理论间的内在联系  相似文献   
7.
The scalar field model of dark energy is established in the double complex symmetric gravitational theory. The universe we live in is taken as the real part of double complex space M^4C(J). The two cases of scalar field (ordinary and phantom scalar field) are discussed in a unified way. Not only can the double Friedmann equations be obtained, but also the equation of state for dark energy, potential V(φ) and scalar field φ can be expressed. Hence, a new method is proposed to study dark energy and the evolution of the universe.  相似文献   
8.
桂元星  张继光  张杨  陈方培 《物理学报》1984,33(8):1129-1136
本文首次用基本方法直接求解Einstein-Maxwell方程,求出了Kerr-Newman度规。 关键词:  相似文献   
9.
In the 5-year WMAP data analysis, a new parametrization form for dark energy equation-of-state was used, and it has been shown that the equation-of-state, w(z), crosses the cosmological-constant boundary w = -1. Based on this observation, in this paper, we investigate the reconstruction of quintom dark energy model. As a single-real-sealarfield model of dark energy, the generalized ghost condensate model provides us with a successful mechanism for realizing the quintom-like behavior. Therefore, we reconstruct this scalar-field quintom dark energy model from the WMAP 5-year observational results. As a comparison, we also discuss the quintom reconstruction based on other specific dark energy ansatzs, such as the CPL parametrization and the holographic dark energy scenarios.  相似文献   
10.
We investigate the electromagnetic perturbation around a stringy black hole. A second-order differential equation is obtained for the perturbation. The variation of the effective potential with r is presented. The complex frequencies of the quasinormal modes of electromagnetic perturbation around a stringy black hole are computed by the third Wentzel-Kramers-Brillouin (WKB) approximation. The results show that the parameters resulted from the compactification of higher dimensions can influence the quasinormal complex frequencies, and the Maxwell field around a stringy black hole damps more slowly than that around a Schwarzschild black hole.  相似文献   
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