Answer:
The steady state theory
Step-by-step explanation:
According to the steady state model of the universe, the universe is continuously expanding while maintaining average density as constant. According to the theory, matter is continuously being formed and creating new stars and galaxies while the old ones are becoming un-observable. There is no beginning or end of time.
On the other hand, the big bang theory describes that the entire matter of the universe was confined in a point and with the big bang, this point started expanding. This happened about 13.8 billion years ago. Of course the density and temperature of the universe was very high at the beginning. In the initial few minutes of the big bang, the universe expanded rapidly which resulted in the decrease in its density and temperature. After million years, the universe transparent for radiation to freely travel through space. Cosmic Microwave background is the remnant of this early universe and is a strong evidence of the Big Bang Theory. The number of quasars were greater in past than present which shows that universe is evolving with time.