Big bounce is a scientific model about the formation of universe. It is a cyclic type of interpretation of big bang theory of universe . It says big bank happened as a result of the collapse of a previous universe.
Big Bounce theory is not a contradiction to previous Big Bang theory instead it is an expansion to big bang which is expected to happen 1379 Crore (13.798 billion) years back.
"Big Bang Theory: It is scientifically proven theory widely accepted by the scientists. It explains as the expansion of space and time , early hot state, formation of helium, hydrogen and lithium, formation of galaxies"
According to the theory Big Bang is not just a single event and it is a beginning of expansion of space and time of universe and it will follow a a period of contraction which is called as a big bounce. It suggest we are living in a point between this expansion and contraction. Its like waves going up and down. The moving(expanding) objects here is time and space. The space point and time point which we belongs to are moving.
The concept behind quantum theory of Big Bounce is , as density approaches infinity , the behaviour of quantum foam changes. The fundamental physical constants are going to change during the period limits between and after this bounce.
Martin Bojowald , PA State University claimed to mathematically solve the time between and after the Big Bang which leads to supporting the cyclic character and Big Bounce.
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