Further understanding the interaction between dark energy and dark matter: current status and future directions.

The interaction between dark matter and dark energy (DE) can be incorporated into field theory models of DE that have proved successful in alleviating the coincidence problem. We review recent advances in this field, including new models and constraints from different astronomical data sets. We show that interactions are allowed by observations and can reduce the current tensions among different measurements of cosmological parameters.

Dark matter and dark energy interactions: theoretical challenges, cosmological implications and observational signatures.

Models where dark matter and dark energy interact with each other have been proposed to solve the coincidence problem. We review the motivations underlying the need to introduce such interaction, its influence on the background dynamics and how it modifies the evolution of linear perturbations. We test models using the most recent observational data and we find that the interaction is compatible with the current astronomical and cosmological data.

Measuring Cosmological Bulk Flows via the Kinematic Sunyaev-Zeldovich Effect in the Upcoming Cosmic Microwave Background Maps.

We propose a new method for measuring the possible large-scale bulk flows in the universe from the cosmic microwave background (CMB) maps from the upcoming missions of the Microwave Anistropy Probe (MAP) and Planck. This can be done by studying the statistical properties of the CMB temperature field at many X-ray cluster positions. At each cluster position, the CMB temperature fluctuation will be a combination of the Sunyaev-Zeldovich (SZ) kinematic and thermal components, the cosmological fluctuations, and the instrument noise term.

On the Number Density of Sunyaev-Zeldovich Clusters of Galaxies.

If the mean properties of clusters of galaxies are well described by the entropy-driven model, the distortion induced by the cluster population on the blackbody spectrum of the cosmic microwave background radiation is proportional to the total amount of intracluster gas, while temperature anisotropies are dominated by the contribution of 1014 M middle dot in circle clusters. This result depends marginally on cluster parameters, and it can be used to estimate the number density of clusters with enough hot gas to produce a detectable Sunyaev-Zeldovich effect. Comparing different cosmological models, the relation depends mainly on the density parameter Omegam.