%0 Journal Article
%T Theoretical Constraint on Purely Kinetic k-Essence<br>Theoretical Constraint on Purely Kinetic κ-Essence
%A YANG Rong-Jia
%A ZHANG Shuang-Nan
%A <br>杨荣佳
%A 张双南
%J 中国物理快报
%D 2008
%I 
%X Purely kinetic k-essence models in which the Lagrangian contains only a kinetic factor and does not depend explicitly on the field itself are considered, and a theoretical constraint is obtained: Fx=F0a-3. Under this theoretical constraint, we discuss a kind of purely k-essence with form F(X)=-(1+2Xn)1/2n, which can be considered as the generalized tachyon field, and find that this kind of k-essence is not likely a candidate of dark energy to describe the present accelerated expansion of the Universe. This is contrary to a previous suggestion that k-essence with such a form may be used to describe phantom cosmologies.
%K 95
%K 36
%K +x
%K 98
%K 80
%K -k
%K 98
%K 80
%K Jk<br>宇宙论
%K 动力学
%K 理论约束
%K 微波传播
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=6E709DC38FA1D09A4B578DD0906875B5B44D4D294832BB8E&cid=47EA7CFDDEBB28E0&jid=E27DA92E19FE279A273627875A70D74D&aid=0AE102546F2790D499C762FE727ED874&yid=67289AFF6305E306&vid=C5154311167311FE&iid=CA4FD0336C81A37A&sid=A04F01817ECB9A48&eid=C7DDDE86E6286CD9&journal_id=0256-307X&journal_name=中国物理快报&referenced_num=0&reference_num=33