论文标题
速度性宇宙学中的跨普兰克问题
The Trans-Planckian problem in Tachyacoustic Cosmology
论文作者
论文摘要
我们研究了宇宙学的速囊模型，为此，尺度不变的扰动频谱是通过静光速度而不是加速扩张产生的，例如在通货膨胀的情况下。我们在声学范围的大小上得出了两个边界，这些边界限制了速度进化的持续时间，从而限制了原始扰动的产生。我们表明，现有模型无法解决地平线问题，而不会违反所有物理量表（例如哈勃参数，压力和量子模式冻结并成为经典的长度尺度）的条件。
We study Tachyacoustic models of cosmology, for which a scale-invariant perturbation spectrum is generated via superluminal sound speed instead of accelerated expansion, as in the case of inflation. We derive two bounds on the size of acoustic horizon which constrain the duration of tachyacoustic evolution, and therefore generation of primordial perturbations. We show that existing models cannot solve the horizon problem without violating the condition that all physical scales -- such as the Hubble parameter, the pressure, and the length scale at which quantum modes freeze out and become classical -- be sub-Planckian.
