Instability of an emergent universe
Instability of an emergent universe
复制标题
新兴宇宙的不稳定性
DOI：
10.1088/1475-7516/2014/05/006
复制
发表时间：
2014
影响因子：
6.4
通讯作者：
A. Vilenkin
中科院分区：
文献类型：
--
作者：
Audrey T. Mithani;A. Vilenkin
圈量子宇宙学有效方程的振荡解被认为是"永恒的种子"，为新兴宇宙场景提供了一个可能的起点。我们研究了一个特定的模型的稳定性，来源于一个均匀的无质量标量场和一个负的宇宙学常数，相对于小扰动和量子崩溃。我们发现，该模型具有扰动稳定和不稳定的解决方案，这两种类型的解决方案占据了重要的区域的参数空间。所有的解决方案是不稳定的崩溃量子隧穿到零尺寸。我们讨论的可能性，从崩溃产生的状态是非奇异的，所以它可能隧道回振荡制度。我们认为，宇宙很可能演变到非常大的尺寸与大粒子占领数的状态。
Oscillating solutions to the effective equations of Loop Quantum Cosmology have been suggested for the role of an `eternal seed', providing a possible starting point for the emergent universe scenario. We investigate the stability of a particular model, sourced by a homogeneous massless scalar field and a negative cosmological constant, with respect to small perturbations and to quantum collapse. We find that the model has perturbatively stable and unstable solutions, with both types of solutions occupying significant regions of the parameter space. All solutions are unstable with respect to collapse by quantum tunneling to zero size. We discuss the possibility that the state resulting from the collapse is non-singular, so it may tunnel back to the oscillating regime. We argue that the universe is then likely to evolve to states of very large size with large particle occupation numbers.