Dear Colleagues,

The first modern cosmological models emerged soon after the discovery of general relativity, putting the study of the Universe as a whole on the firm grounds of an empirically testable, coherent science. In the century since then, cosmology has developed into a precision discipline able to explain the evolution of the Universe in several of its aspects. The goal is under the way, but far than ended. The most stringent open questions remain the nature of dark matter (DM) and of dark energy (DE), and whether General Relativity holds on large cosmological scales.

Of course, many independent observation (anisotropies in CMB, large structure, SNIa data, gravitational lensing, galaxy rotational curves etc.) confirm the necessity of the introduction of these dark components.

However, the existence itself of the most likely DM candidates seem to have been seriously challenged by experiments and or astrophysical observations: e.g. supersymmetric DM and WIMPs by LHC; by LUX, PandaX-II and Xenon100; MACHOs by microlensing. Sterile neutrinos by IceCube and high redshift objects. The properties of the DM in galaxies are presently badly explainable by current theoretical scenarios. At present the nature of DM remains a mystery.

Understanding DE poses an even bigger challenge. Although the cosmological constant may explain the accelerated cosmic expansion, its physical interpretation (as vacuum energy) remains doubtful. Question comes what kind of fields can be responsible for the accelerated cosmic expansion. Several scalar field models of DE induce new type of space-time singularities (e.g. soft singularities). Alternative gravitational theories (e.g. scalar-tensor theories, the emergent gravity model of Verlinde) have been also proposed with the purpose to explain the dark sector.

We invite colleagues to submit papers on the topics:

1: The nature of Dark matter and DE

2: Present/future experiments and observations related to DM, DE and their gravitational effects.

3: Models on DM and DE including the alternative gravitational theories, new fields and their possible interaction with the particles of standard model.

4: Evolution of the Universe, cosmological perturbations, formation of nonlinear structures, first objects.

5: Inflation, initial structure, primordial gravitational waves.

6: Primordial black/white holes, their formation and gravitational waves, their effects on the synthesis of light elements.

7: Anisotropic cosmological models and their perturbations.

8: Exotic singularities, wormholes occurring in cosmological models and in virialized structure.

Dr. Zoltan Keresztes
Prof. Lorenzo Iorio
Prof. Paolo Salucci
Prof. Emmanuel Saridakis
Guest Editors