论文标题
负能量密度的宇宙演化
Cosmological evolution with negative energy densities
论文作者
论文摘要
对于一般数量的空间维度，我们研究了由宇宙常数和带有状态的压力方程的来源驱动的宇宙学动力学。假定对于这两个来源，能量密度可以是正的或负的。为平面模型提供了宇宙方程的精确解。对于具有弯曲空间和零宇宙常数的模型，通用溶液以超几何函数的形式表示。针对状态参数方程的所有值描述了定性演化。我们指定该参数的值以及宇宙常数和物质能量密度的符号的组合，其宇宙动力学是非源头的。考虑一个示例，其用双曲线真空的极化引起的正宇宙常数和负物质密度。
For general number of spatial dimensions we investigate the cosmological dynamics driven by a cosmological constant and by a source with barotropic equation of state. It is assumed that for both those sources the energy density can be either positive or negative. Exact solutions of the cosmological equations are provided for flat models. For models with curved space and with zero cosmological constant the general solutions are expressed in terms of the hypergeometric function. The qualitative evolution is described for all values of the equation of state parameter. We specify the values of that parameter and the combinations of the signs for the cosmological constant and matter energy density for which the cosmological dynamics is nonsingular. An example is considered with positive cosmological constant and negative matter energy density induced by the polarization of the hyperbolic vacuum.
