arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0801.0323astro-ph
收藏

化学势和暗能量的性质：幻影的例子

Chemical Potential and the Nature of the Dark Energy: The case of phantom

J. A. S. Lima, S. H. Pereira

备注：
7 pages, 5 figures
发表信息：
Phys.Rev.D78:083504,2008
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

摘要：

假设暗能量是服从状态方程的相对论理想简单流体$p=ωρ$（$ω<0, constant$），研究了可能存在的非零化学势$μ$对暗能量性质的影响.熵条件$S \geq 0$意味着$ω$的可能值很大程度上取决于化学势的大小和符号。对于$μ>0$，$ω$ -参数必须大于-1（禁止真空），而对于$μ< 0$，不仅允许真空，甚至允许类似幻影的行为（$ω<-1$）。在任何情况下，化学势和温度之间的比率保持恒定，即$μ/T=μ_0/T_0$。假设暗能量组分具有玻色子或费米子性质，也提出了谱的一般形式。对于玻色子，$μ$总是负的，并且扩展的维恩定律只允许具有$ω< -1/2$的暗分量，其中包括真空和幻影的情况。同样的情况也发生在$μ<0$的费米分支中。然而，只有当$-1 < ω< -1/2$时，才允许具有$μ>0$的费米子粒子。热力学和统计参数将EoS参数限制为$ω< -1/2$，这一结果令人惊讶地接近于加速由物质和暗能量主导的FRW型宇宙（$ω\lesssim -10/21$）所需的最大值。

英文摘要：

The influence of a possible non zero chemical potential $μ$ on the nature of dark energy is investigated by assuming that the dark energy is a relativistic perfect simple fluid obeying the equation of state (EoS), $p=ωρ$ ($ω<0, constant$). The entropy condition, $S \geq 0$, implies that the possible values of $ω$ are heavily dependent on the magnitude, as well as on the sign of the chemical potential. For $μ>0$, the $ω$-parameter must be greater than -1 (vacuum is forbidden) while for $μ< 0$ not only the vacuum but even a phantomlike behavior ($ω<-1$) is allowed. In any case, the ratio between the chemical potential and temperature remains constant, that is, $μ/T=μ_0/T_0$. Assuming that the dark energy constituents have either a bosonic or fermionic nature, the general form of the spectrum is also proposed. For bosons $μ$ is always negative and the extended Wien's law allows only a dark component with $ω< -1/2$ which includes vacuum and the phantomlike cases. The same happens in the fermionic branch for $μ<0$. However, fermionic particles with $μ>0$ are permmited only if $-1 < ω< -1/2$. The thermodynamics and statistical arguments constrain the EoS parameter to be $ω< -1/2$, a result surprisingly close to the maximal value required to accelerate a FRW type universe dominated by matter and dark energy ($ω\lesssim -10/21$).

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

↑