prof. dr hab. Mariusz P. Dąbrowski (IF US)

Weak singularities in Friedmann cosmology and varying physical constants

I will present a variety of non-standard (non-big-bang/big-crunch) cosmological singularities such as big-rips, sudden future singularities, finite scale factor singularities, big-separations, w-singularities (or type II-V), their variants and generalizations. I will show that most of them are of a weak type and are not characterized by geodesic incompletness. Besides, some of them may fit observational data (supernovae, baryon acoustic oscillations, CMB, redshift drift) and so serve as the dark energy. I will also discuss the influence of the possible variation of the fundamental physical constants such as the gravitational constant G and the velocity of light c onto the nature of these singularities.