标题： 宇宙过渡对密度扰动演化的影响 显示英文标题

标题： The influence of cosmological transitions on the evolution of density perturbations

摘要： 我们研究了再加热和相等性转变对超视界密度扰动和引力波的影响。 最近对暴胀宇宙学中大尺度扰动的“标准结果”的批评得到了纠正。 声称超视界模量幅度的“守恒定律”是空洞的说法被证明是错误的。 对于尖锐的转变，即压力跳跃，我们重新推导了Deruelle-Mukhanov接合条件。 对于平滑的转变，我们纠正了Grishchuk最近得到的一个结果。 我们表明，接合条件并不关键，因为在再加热转变过程中压力是连续的。 问题出在，扰动度规没有正确地通过平滑的再加热转变演化。 最后，我们在Grishchuk的平滑（再加热）转变中得出了“标准结果”。 显示英文摘要

摘要： We study the influence of the reheating and equality transitions on superhorizon density perturbations and gravitational waves. Recent criticisms of the `standard result' for large-scale perturbations in inflationary cosmology are rectified. The claim that the `conservation law' for the amplitude of superhorizon modes was empty is shown to be wrong. For sharp transitions, i.e. the pressure jumps, we rederive the Deruelle-Mukhanov junction conditions. For a smooth transition we correct a result obtained by Grishchuk recently. We show that the junction conditions are not crucial, because the pressure is continuous during the reheating transition. The problem occurred, because the perturbed metric was not evolved correctly through the smooth reheating transition. Finally, we derive the `standard result' within Grishchuks's smooth (reheating) transition.