The discovery by Hubble that the galaxies are receding from us at a speed which is proportional to their distance led consequently to the establishment of the Big Bang theory.
This theory presents some apparent contradictions or paradoxes that can be explained taking into account the relativistic geometry.
Cosmos expands at the speed of light,
from a single point: it was the Big Bang!
Center or limits absent at all,
geometry shaping the Cosmic Ball