July 17, 2019
We investigate interacting scenarios which belong to a wider class, since they include a dynamical dark energy component whose equation of state follows various one-parameter parametrizations. We confront them with the latest observational data from Cosmic Microwave Background (CMB), Joint light-curve (JLA) sample from Supernovae Type Ia, Baryon Acoustic Oscillations (BAO), Hubble parameter measurements from Cosmic Chronometers (CC) and a gaussian prior on the Hubble paramete...
January 21, 2002
We explore the prospects for using future supernova observations to probe the dark energy. We focus on quintessence, an evolving scalar field that has been suggested as a candidate for the dark energy. After simulating the observations that would be expected from the proposed SuperNova / Acceleration Probe satellite (SNAP), we investigate two methods for extracting information about quintessence from such data. First, by expanding the quintessence equation of state as w_Q(z) ...
August 15, 2018
We derive two field theory models of interacting dark energy, one in which dark energy is associated with the quintessence and another in which it is associated with the tachyon. In both, instead of choosing arbitrarily the potential of scalar fields, these are specified implicitly by imposing that the dark energy fields must behave as the new agegraphic dark energy. The resulting models are compared with the Pantheon supernovae sample, CMB distance information from Planck 20...
August 7, 2008
We consider the cosmological constraints on theories in which there exists a nontrivial coupling between the dark matter sector and the sector responsible for the acceleration of the universe, in light of the most recent supernovae, large scale structure and cosmic microwave background data. For a variety of models, we show that the strength of the coupling of dark matter to a quintessence field is constrained to be less than 7% of the coupling to gravity. We also show that l...
July 19, 2022
We have re-investigated Cosmology involving interaction between Dark matter and Dark Energy in the light of a new parametrization. The new parametrization is based on the hypothesis that when Dark matter and Dark Energy will interact, Dark matter will dilute in a different manner than standard non-interacting scenario. We re-built the Cosmological equations with this new parametrization. Observational constraints on the traditional Cosmological parameters and new parameters h...
December 4, 2002
We present cosmological parameter constraints on flat cosmologies dominated by dark energy using various cosmological data including the recent Archeops angular power spectrum measurements. A likelihood analysis of the existing Cosmic Microwave Background data shows that the presence of dark energy is not requested, in the absence of further prior. This comes from the fact that there exist degeneracies among the various cosmological parameters constrained by the Cosmic Microw...
April 2, 2024
We present a comprehensive reassessment of the state of Interacting Dark Energy (IDE) cosmology, namely models featuring a non-gravitational interaction between Dark Matter (DM) and Dark Energy (DE). To achieve high generality, we extend the dark sector physics by considering two different scenarios: a non-dynamical DE equation of state $w_0\neq-1$, and a dynamical $w(a)=w_0+w_a(1-a)$. In both cases, we distinguish two different physical regimes resulting from a phantom or qu...
June 27, 2014
We show that a general late-time interaction between cold dark matter and vacuum energy is favoured by current cosmological datasets. We characterize the strength of the coupling by a dimensionless parameter $q_V$ that is free to take different values in four redshift bins from the primordial epoch up to today. This interacting scenario is in agreement with measurements of cosmic microwave background temperature anisotropies from the Planck satellite, supernovae Ia from Union...
October 21, 2004
In this paper I discuss some of the phenomenologies of models of the dark energy interacting with the ordinary matter. After a very brief review about the current constraint on the equation of the state of the dark energy from the SN and a new scenario of dark energy {\it the Quintom}, I present models of Quintessential Baryo(Lepto)genesis, Quintessino dark matter and mass varying neutrinos in details.
November 9, 2013
Recently, the Planck collaboration has released the first cosmological papers providing the high resolution, full sky, maps of the cosmic microwave background (CMB) temperature anisotropies. It is crucial to understand that whether the accelerating expansion of our universe at present is driven by an unknown energy component (Dark Energy) or a modification to general relativity (Modified Gravity). In this paper we study the coupled dark energy models, in which the quintessenc...