Abstract

We consider a 4-dimensional FRW Universe in the framework of fractal cosmology, where the space-time is assumed to be fractal, and the dimensionality of space changes with time. So, in fractal cosmology, the Universe and its matter components act in a fractal way over a full range of scales. Firstly, the modified Chaplygin gas and then the generalized cosmic Chaplygin gas are taken as the cosmic substratum. In these scenarios, the matter-antimatter asymmetry is investigated by two gravitational mechanisms: baryogenesis and leptogenesis. For gravitational baryogenesis, we find the ratio of baryon number density to entropy in both gases graphically. Also, for gravitational leptogenesis, we find the ratio of lepton number density to entropy in both gases graphically.