Testing Oscillating Primordial Spectrum and Oscillating Dark Energy with Astronomical Observations

TL;DR

This study uses current astronomical data to constrain oscillating features in the primordial scalar spectrum and dark energy's equation of state, finding they are still compatible with observations and could be better tested with future data.

Contribution

The paper provides the first comprehensive analysis constraining oscillating primordial spectra and dark energy oscillations using combined observational data.

Findings

Oscillating primordial spectrum amplitude constrained to |n_amp|<0.116

Oscillating dark energy equation of state constrained to |w_amp|<0.232

Oscillatory features remain compatible with current observations

Abstract

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.