A FURTHER DISCUSSION ON THE FORCES THAT CAUSE THE UNIVERSE TO EXPAND

This article makes more contribution on the discussion about the forces causing the universe to expand. It shows that the stars’ radiation pressure force can not only push small matters such as interstellar dust away, but also can push big celestial bodies away. Gravitational lens effect can further help during the process of radiation pressure forces pushing away big celestial bodies. Then the interstellar dusts and big celestial bodies will exert continuous pulling forces to nearby bigger celestial bodies and cause the entire universe to expand. So after the total radiation of stars inside the universe decreases, the universe will start to contract. Another expansion may begin when the universe contract to a certain degree. Thus there can be a cycle of repeated expansion & contractions. When all the fusion materials are used up to a degree so that another expansion cannot happen, the universe will eventually contract together and form a hugest black hole. If this black hole becomes unstable, it will explode and form another universe.