Physics – High Energy Physics – High Energy Physics - Theory
Scientific paper
2006-10-17
Class.Quant.Grav.24:3799-3811,2007
Physics
High Energy Physics
High Energy Physics - Theory
13 pages, one figure, typo corrected, references added, the contents and results enhanced, but previous results remains no cha
Scientific paper
10.1088/0264-9381/24/15/002
We generally investigate the scalar field model with the lagrangian $L=F(X)-V(\phi)$, which we call it {\it General Non-Canonical Scalar Field Model}. We find that it is a special square potential(with a negative minimum) that drives the linear field solution($\phi=\phi_0t$) while in K-essence model(with the lagrangian $L=-V(\phi)F(X)$) the potential should be taken as an inverse square form. Hence their cosmological evolution are totally different. We further find that this linear field solutions are highly degenerate, and their cosmological evolutions are actually equivalent to the divergent model where its sound speed diverges. We also study the stability of the linear field solution. With a simple form of $F(X)=1-\sqrt{1-2X}$ we indicate that our model may be considered as a unified model of dark matter and dark energy. Finally we study the case when the baryotropic index $\gamma$ is constant. It shows that, unlike the K-essence, the detailed form of F(X) depends on the potential $V(\phi)$. We analyze the stability of this constant $\gamma_0$ solution and find that they are stable for $\gamma_0\leq1$. Finally we simply consider the constant c_s^2 case and get an exact solution for F(X)
Fang Wei
Huang Zeng-Guang
Lu Hui-Qing
No associations
LandOfFree
Cosmologies with General Non-Canonical Scalar Field does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Cosmologies with General Non-Canonical Scalar Field, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cosmologies with General Non-Canonical Scalar Field will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-390582