论文标题
封闭的宇宙中Starobinsky通胀的量子重力发作
Quantum gravitational onset of Starobinsky inflation in a closed universe
论文作者
论文摘要
最近的宇宙微波背景观察结果有利于封闭宇宙中低能量表通货膨胀模型。但是,众所周知,此类模型中通货膨胀的发作是严重问题的。特别是,这样的宇宙在几秒钟内回想起,当普朗克政权在初始条件下时,遇到了很大的紧缩奇异性。我们表明,在量子重力框架中可以成功克服低能通货膨胀模型中通货膨胀发作的问题,在这种量子重力框架中,大爆炸/大弯曲奇异性得到解决,并且在通货膨胀之前存在非单独的环环进化。作为一个例子,我们考虑了循环量子宇宙学中的一个模型,并证明了封闭宇宙中低能量表通胀的成功开始是Starobinsky通货膨胀模型,从各种初始条件开始,在经典理论中是不可能的。为了进行比较,我们还研究了在类似的不利条件下$ ϕ^2 $通货膨胀模型中通货膨胀的开始。具有量子重力效应的发达前阶段被证明是由弹跳和回忆的非相同循环组成的,导致类似滞后现象,这在创造适当的通货膨胀条件中起着某些非单一循环后出现的适当条件而起着重要作用。我们的分析表明,经典理论中的张力构成相当于封闭的FLRW宇宙在低能量表膨胀开始的情况下,可以成功解决循环量子宇宙学。
Recent cosmic microwave background observations favor low energy scale inflationary models in a closed universe. However, onset of inflation in such models for a closed universe is known to be severely problematic. In particular, such a universe recollapses within a few Planck seconds and encounters a big crunch singularity when initial conditions are given in the Planck regime. We show that this problem of onset of inflation in low energy scale inflationary models can be successfully overcome in a quantum gravitational framework where the big bang/big crunch singularities are resolved and a non-singular cyclic evolution exists prior to inflation. As an example we consider a model in loop quantum cosmology and demonstrate that the successful onset of low energy scale inflation in a closed universe is possible for the Starobinsky inflationary model starting from a variety of initial conditions where it is impossible in the classical theory. For comparison we also investigate the onset of inflation in the $ϕ^2$ inflationary model under similar unfavorable conditions. The pre-inflationary phase with quantum gravity effects is shown to be composed of non-identical cycles of bounces and recollapses resulting in a hysteresis-like phenomenon, which plays an important role in creating suitable conditions for inflation to occur after some number of non-singular cycles. Our analysis shows that the tension in the classical theory amounting to the unsuitability of closed FLRW universes with respect to the onset of low energy scale inflation can be successfully resolved in loop quantum cosmology.