Dark energy and fate of the Universe  

作　　者：LI XiaoDong WANG Shuang HUANG QingGuo ZHANG Xin LI Miao 

机构地区：[1]Department of Modern Physics,University of Science and Technology of China,Hefei 230026,China [2]Institute of Theoretical Physics,Chinese Academy of Sciences,Beijing 100190,China [3]Key Laboratory of Frontiers in Theoretical Physics,Chinese Academy of Sciences,Beijing 100190,China [4]Department of Physics,College of Sciences,Northeastern University,Shenyang 110004,China [5]Center for High Energy Physics,Peking University,Beijing 100080,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2012年第7期1330-1334,共5页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the Project of Knowledge Innovation Program of Chinese Academy of Sciences;the National Natural Science Foundation of China (Grant Nos. 11105053, 10705041, 10975032, 11175042,10535060, 10975172 and 10821504);the National Ministry of Education of China (Grant Nos. NCET-09-0276 and N100505001);the National Basic Research Program of China (Grant No. 2007CB815401)

摘　　要：We explore the ultimate fate of the Universe by using a divergence-free parametrization for dark energy w（z）=w0＋wa, [In（2 ＋ z） / （1 ＋ z） - In 2] . Unlike the Chevallier-Polarski-Linder parametrization, this parametrization has well behaved, bounded behavior for both high redshifts and negative redshifts, and thus can genuinely cover many theoretical dark energy models. Alter constraining the parameter space of this parametrization by using the current cosmological observations, we find that, at the 95.4% confidence level, our Universe can still exist at least 16.7 Gyr before it ends in a big rip. Moreover, for the phantom energy dominated Universe, we find that a gravitationally bound system will be destroyed at a time t = P√2｜ 1 ＋ 3w（ 1）] / [6π] 1 ＋ w（-1）｜], where P is the period of a circular orbit around this system, before the big rip.We explore the ultimate fate of the Universe by using a divergence-free parametrization for dark energy w(z)=w0+wa[ln(2+z)/(1+z)-ln2]. Unlike the Chevallier-Polarski-Linder parametrization, this parametrization has well behaved, bounded behavior for both high redshifts and negative redshifts, and thus can genuinely cover many theoretical dark energy models. After constraining the parameter space of this parametrization by using the current cosmological observations, we find that, at the 95.4% confidence level, our Universe can still exist at least 16.7 Gyr before it ends in a big rip. Moreover, for the phantom energy dominated Universe, we find that a gravitationally bound system will be destroyed at a time t≌P(2|1+3w(-1)|)～1/2/[6π|1+w(-1)|], where P is the period of a circular orbit around this system, before the big rip.

关 键 词：dark energy dynamical evolution fate of the Universe 

分 类 号：P145.9[天文地球—天体物理]