论文标题
来自DHOST宇宙学的新兴宇宙和创世纪
Emergent Universe and Genesis from the DHOST Cosmology
论文作者
论文摘要
在本文中，我们提出了一个新兴的宇宙场景，该场景可以源自DHOST宇宙学。宇宙在过去的过去就像常规的Galileon Genesis一样渐近地开始了Minkowski，但在后期却以辐射为主的时期发展，因此，宇宙具有正常的Galileon Genesis中没有优美的出口。我们分析了宇宙学扰动的行为，并表明标量和张量模式都摆脱了梯度不稳定性问题。我们进一步分析了在各种情况下产生的原始标量频谱，并讨论是否可以实现量表不变性。
In this article, we present an emergent universe scenario that can be derived from DHOST cosmology. The universe starts asymptotically Minkowski in the far past just like the regular Galileon Genesis, but evolves to a radiation dominated period at the late stage, and therefore, the universe has a graceful exit which is absent in the regular Galileon Genesis. We analyze the behavior of cosmological perturbations and show that both the scalar and tensor modes are free from the gradient instability problem. We further analyze the primordial scalar spectrum generated in various situations and discuss whether a scale invariance can be achieved.
