Scientists are messing with our poor simple minds again! Young, hip (relatively speaking) physicists are making a case that the universe may not have started with the “big bang” at all. They believe that the universe may undergo endless cycles of evolution in infinite space and time.
One hotly disputed theory is that there is no beginning, and no end because space and time have always existed in an endless cycle of expansion and rebirth. They point out that the expansion of the universe is accelerating, as astronomers have recently observed and that after trillions of years, expansion eventually stalls, new matter and radiation is created, and then the cycle begins yet again.
from: Daily Galaxy