In this paper we revisit the issue of determining the oscillating primordial scalar power spectrum and oscillating equation of state of dark energy from the astronomical observations. By performing a global analysis with the Markov Chain Monte Carlo method, we find that the current observations from five-year WMAP and SDSS-LRG matter power spectrum, as well as the "union" supernovae sample, constrain the oscillating index of primordial spectrum and oscillating equation of state of dark energy with the amplitude less than $|n_{\rm amp}|<0.116$ and $|w_{\rm amp}|<0.232$ at 95% confidence level, respectively. This result shows that the oscillatory structures on the primordial scalar spectrum and the equation of state of dark energy are still allowed by the current data. Furthermore, we point out that these kinds of modulation effects will be detectable (or gotten a stronger constraint) in the near future astronomical observations, such as the PLANCK satellite, LAMOST telescope and the currently ongoing supernovae projects SNLS.
Primordial Physics in the Nonlinear Universe: Revealing the oscillating halo bias from cosmological collider models
University of Chicago（芝加哥大学）；Kavli Institute for Cosmological Physics, University of Chicago（宇宙学物理卡弗里研究所，芝加哥大学）；Perimeter Institute for Theoretical Physics（理论物理 perimeter 研究所）
Institute for Nuclear Research of the Russian Academy of Sciences（俄罗斯科学院核物理研究所）；National Research Nuclear University MEPhI（国立核研究大学莫斯科工程物理学院）；Sternberg Astronomical Institute, Lomonosov Moscow State University（莫斯科罗蒙诺索夫国立大学斯捷尔伯格天文学研究所）
Cosmological consequences of a scalar field with oscillating equation of state. III. Unifying inflation with dark energy and small tensor-to-scalar ratio
研究了Tián [ \href{https://doi.org/10.1103/PhysRevD.101.063531}{Phys. Rev. D {\bf 101}, 063531 (2020)} ]提出的振荡暗能量模型的暴胀效应，该模型旨在解决多重加速宇宙（MAU）的宇宙学符合问题.我们指出，通货膨胀的动力学属于慢卷通货膨胀。标量扰动和张量标量比$r$的光谱指数被证明是与当前的\textit{Planck}测量一致。特别是，该模型预测的$r\sim10^{-7}$远低于观察限。这一结果促使我们探索一般MAU中$r$的微小性。我们提出了一个典型的推广的原始模型和证明$r<0.01$一般。到目前为止，原始引力波的零探测为MAU提供了间接证据。暴胀结束后，标量场不再是局部极小值，而是向无穷远滚动，同时其状态方程以大于$1/3$的平均值振荡。在这个框架中，我们证明了在暴胀结束时引力粒子的产生能够重新加热宇宙。
