Oscillations in the dark energy EoS: new MCMC lessons

Understand

We study the possibility of detecting oscillating patterns in the equation of state (EoS) of the dark energy using different cosmological datasets.

• We follow a phenomenological approach and study three different oscillating models for the EoS, one of them periodic and the other two damped (proposed here for the first time).
• All the models are characterised by the amplitude value, the centre and the frequency of oscillations.
• In contrast to previous works in the literature, we do not fix the value of the frequency to a fiducial value related to the time extension of chosen datasets, but consider a discrete set of values, so to avoid arbitrariness and try and detect any possible time period in the EoS.