Related papers: On Evidence for Elastic Interactions in the Dark S…
We examine the possibility of "soft cosmology", namely small deviations from the usual framework due to the effective appearance of soft-matter properties in the Universe sectors. One effect of such a case would be the dark energy to…
We examine the effects of possible phenomenological interactions between dark energy and dark matter on cosmological parameters and their efficiency in solving the coincidence problem. We work with two simple parameterizations of the…
In this study, we consider dark matter and dark energy as grand-canonical systems which are open, non-equilibrium coupled, and interacting systems. For the first time, we propose a new more realistic interaction scheme to explain dynamics…
Diverse cosmological and astrophysical observations strongly hint at the presence of dark matter and dark energy in the Universe. One of the main goals of Cosmology is to explain the nature of these two components. It may well be that both…
We investigate cosmological constraints on an energy density contribution of elastic dark matter self-interactions characterized by the mass of the exchange particle and coupling constant. Because of the expansion behaviour in a…
Coupled dark matter-dark energy scenarios are modeled via a dimensionless parameter $\xi$, which controls the strength of their interaction. While this coupling is commonly assumed to be constant, there is no underlying physical law or…
Excess emission over expected diffuse astrophysical backgrounds in the direction of the Galactic center region has been claimed at various wavelengths, from radio to gamma rays. Among particle models advocated to explain such observations,…
I consider couplings between the dark energy and dark matter sectors. I describe how the existence of an adiabatic regime, in which the dark energy field instantaneously tracks the minimum of its effective potential, opens the door for a…
Recent astrophysical observations have motivated novel theoretical models of the dark matter sector. A class of such models predicts the existence of GeV scale cosmic strings that communicate with the standard model sector by Aharonov-Bohm…
The answer is Yes! We indeed find that interacting dark energy can alleviate the current tension on the value of the Hubble constant $H_0$ between the Cosmic Microwave Background anisotropies constraints obtained from the Planck satellite…
We investigate interacting dark energy models in the framework of fractal cosmology. We discuss a fractal FRW universe filled with the dark energy and dark matter which interact with each other. We obtain the equation for the relative…
The origin of the accelerated expansion of the universe is still unclear and new physics is needed on cosmological scales. We propose and test a novel interpretation of dark energy as originated by an elastic strain due to a cosmic defect…
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 sectors, consisting of new, light, weakly-coupled particles that do not interact with the known strong, weak, or electromagnetic forces, are a particularly compelling possibility for new physics. Nature may contain numerous dark…
We consider a set of non-linear interactions between dark matter and dark energy which comprises couplings proportional to products of (powers of) the energy densities of both dark components and of the total energy. We demonstrate that…
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…
Despite the astonishing success of standard $\Lambda$CDM cosmology, there is mounting evidence for a tension with observations at small and intermediate scales. We introduce a simple model where both cold dark matter (DM) and sterile…
The coincidence problems and other dynamical features of dark energy are studied in cosmological models with variable cosmological parameters and in models with the composite dark energy. It is found that many of the problems usually…
Recent DESI baryon acoustic oscillation data reveal deviations from $\Lambda$CDM cosmology, conventionally attributed to dynamical dark energy (DE). We demonstrate that these deviations are equally, if not better, explained by interactions…
Using late-Universe observations, we demonstrate that freeing dark energy and dark matter equations of state (EoS) dramatically alters the inferred strength and direction of their interactions. When dark sector EoS are fixed to…