Different theories about the universe's beginning has been offered by numerous scientists to try and show that the Big Bang isn't really the start of it all. Most of the time though, these theories never get accepted as reality because they lack the scientific data necessary to be able to test their feasibility.  One theory regarding the universe's beginning has surfaced, and there is a possibility for it to be accepted because of the kind of scientific data it is able to provide.

Scientists at Penn State has used quantum gravitational calculations in order to search if time existed before the believed beginning of the universe (Big Bang), and they were able to come up with the Big Bounce Theory. Scientists Abhay Ashtekar, Tomasz Pawlowski, and Parmpreet Singh have come up with this theory using quantum tools that were not available during the time the Big Bang theory was being developed.

In this research, the team of scientists was able to prove that there was a contracting universe that existed before the Big Bang, and it had space-time geometry that was similar to that of the current expanding universe. In the said universe before the Big Bang, the gravitational forces pulled the universe inward to the point that this gravity became repulsive rather than attractive, causing the Big Bounce.

The team used the same quantum modifications of Einstein's cosmological equations in testing this quantum bounce, and they even repeated the simulations using different parameter values to see if the results might change. The result though was the same, showing that the Big Bounce possibly happened.