Understanding the science behind the universe’s mysterious phenomena has always been a popular topic, connecting diverse branches of physics. From understanding its contents through studying the universe’s structure, to how it was formed. Yet gravity, even though a fundamental concept of nature, has not been fully understood and still presents us with unexplored mysteries. Described as a force by Newton, it is now described somewhat abstractly by Einstein in his theory of General Relativity, as the bending of a spacetime fabric due to the presence of masses, such as planets and stars. This was a revolutionary discovery, for example in the discovery of gravitational waves and its technological applications (most notably the GPS). Observations have continuously proved the validity of the general theory of relativity. Yet, no theory is perfect. As human technology becomes more advanced, precise astrophysical and cosmological data slowly shed light on the issues of Einstein’s theory. No one yet truly knows how gravity works at the smallest scales, that is, how gravity works with quantum mechanics. This is crucial to understand what happened in the first few moments after the Big...