Before the 20th century, people believed that looked the same way forever. But in 1929, the universe had existed forever, and had astronomers made a startling discovery. L ooking through their telescopes they noticed moving away from each other at enormous speed - our universe is expanding! If our universe is expanding, then logically at some point in the past the entire universe was contained in a single point in space. The Big Bang Theory states that about 14 billion years ago, our universe exploded out of nowhere from a single point and it has been expanding ever since to form the universe we know today. Our universe, in other words, has not existed forever. It had a definite beginning. Before our universe came into existence there was nothing no time, space, matter, energy ... nothing! The Big Bang created time, space and matter. The Big Bang Theory is currently the most widely accepted hypothesis for the origin of the universe. However, it still leaves many questions unanswered. For instance, it doesn't explain why the big bang happened in the first place.The Cyclical Universe Theory. The Cyclical Universe Theory addresses the question, "What caused the big bang?" The answer it gives is the collapse and expansion of a prior universe. According to the Cyclical Universe Theory, our universe began when another universe collapsed violently into a single point then exploded out again. Trillions of years from now, our own universe will stop expanding and begin to contract. Eventually, it will also collapse into a single point and explode out again giving rise to a new universe. Our universe is therefore just the latest in an endless series. Countless universes have preceded this universe and countless others will follow it. Space and time had no beginning. Cycles of expansion, contraction, collapse, and explosion have been going on forever.According to the Multiple Universe Theory, what we have been calling the universe is actually nothing like we thought! It is just a single bubble in an infinite number of universes. We are actually living in a multiverse consisting of trillions of universes. The multiverse has existed forever, and each universe in it is different. The main motivation behind the Multiple Universe Theory is to provide an explanation as to why our universe seems to be so perfectly suited towards supporting life. For many people, this fact demands an explanation. They feel it is too much of a coincidence that the conditions in our universe just happen to be right to make life possible. The Multiple Universe Theory states that there is nothing mysterious about this. There are trillions upon trillions of universes in the multiverse and therefore at least a few of them will have conditions that make life possible. We simply happen to be living in one of these universes. Составить 6 вопросов (Желательно с переводом )​