Related papers: Interacting Dark Matter and Dark Energy
The two most popular candidates for dark energy, i.e. a cosmological constant and quintessence, are very difficult to distinguish observationally, mostly because the quintessence field does not have sizable fluctuations. We study a scalar…
The strange behaviour of the universe's dark sector offers us the flexibility to address cosmological problems with different approaches. Using this flexibility, we consider a possible exchange of energy among the dark sector components as…
Dark energy affects the CMB through its perturbations and affects both CMB and Sn-Ia through its background evolution. Using recent CMB and Sn-Ia data sets, together with the most general parameterization of the dark energy equation of…
High precision cosmological observations in last decade suggest that about 70% of our universe's energy density is in so called "Dark Energy" (DE). Observations show that DE has negative effective pressure and therefore unlike conventional…
The decay and annihilation cross sections of dark matter particles may depend on the value of a chameleonic scalar field that both evolves cosmologically and takes different values depending on the local matter density. This possibility…
The main aim of this work is to explore the possibility that cold dark matter (CDM) and early dark energy (EDE) can be described by canonical scalar fields that are coupled at the level of its conservation equations. The formalism covers…
We consider a dark energy model with a relation between the equation of state parameter $w$ and the energy density parameter $\Omega_\phi$ derived from thawing scalar field models. Assuming the variation of the fine structure constant is…
We present cosmological perturbation theory in neutrino probe interacting dark-energy models, and calculate cosmic microwave background anisotropies and matter power spectrum. In these models, the evolution of the mass of neutrinos is…
We outline a dynamical dark energy scenario whose signatures may be simultaneously tested by astronomical observations and laboratory experiments. The dark energy is a field with slightly sub-gravitational couplings to matter, a logarithmic…
We study the dynamical aspects of dark energy in the context of a non-minimally coupled scalar field with curvature and torsion. Whereas the scalar field acts as the source of the trace mode of torsion, a suitable constraint on the torsion…
We study cosmological models involving scalar fields coupled to radiation and discuss their effect on the redshift evolution of the cosmic microwave background temperature, focusing on links with varying fundamental constants and dynamical…
We study in some detail an interacting cosmological model based on two canonical scalar fields starting from a Lagrangian description. Contrary to other more phenomenological approaches where non-relativistic matter and dark energy are…
The existence and detection of scalar fields could provide solutions to long-standing puzzles about the nature of dark matter, the dark compact objects at the centre of most galaxies, and other phenomena. Yet, self-interacting scalar fields…
In this talk we present a model of the universe in which dark energy is modelled explicitely with both a dynamical quintessence field and a cosmological constant. Our results confirm the possibility of a collapsing universe (for a given…
The standard model of cosmology relies on the existence of two components, "dark matter" and "dark energy", which dominate the expansion of the Universe. There is no direct proof of their existence, and their nature is still unknown. Many…
We present evidence that the simplest particle-physics scalar-field models of dynamical dark energy can be separated into distinct behaviors based on the acceleration or deceleration of the field as it evolves down its potential towards a…
The two dark sectors of the universe - dark matter and dark energy - may interact with each other. Background and linear density perturbation evolution equations are developed for a generic coupling. We then establish the general conditions…
Interacting dark energy models may play a crucial role in explaining several important observational issues in modern cosmology and also may provide a solution to current cosmological tensions. Since the phenomenology of the dark sector…
We study a cosmological model in which phantom dark energy is coupled to dark matter by phenomenologically introducing a coupled term to the equations of motion of dark energy and dark matter. This term is parameterized by a dimensionless…
(Abridged) Present cosmological constraints and the absence of a direct detection and identification of any dark matter particle candidate leave room to the possibility that the dark sector of the Universe be actually more complex than it…