One interesting issue in the study of cosmology is the issue of the origin. In this field, two major models were suggested, which are: the big bang (commonly referred to as the standard model), and the steady state model. A number of scientific discoveries in the middle of this century came to reinforce the standard model, in particular the discovery of the red shift of the galaxies (the expansion of the universe), and the discovery of the cosmic background radiation.

According to the big bang model, the universe started at a certain moment (t = 0) 15 billion years ago. The big bang was a huge explosion; not an explosion similar to those we see on earth. It was an explosion in which matter was created from energy, and the cooling of this infinitely hot matter led to the formation of the large universe we live in it today.

In spite of the large amount of scientific evidence that corroborate the big bang model, still a lot of myteries have remained unsolved. It is the future hope of this field, in which mathematics and physics mix, to produce a theoretical model to provide us with an explanation for the creation of the universe.