Due to a lack of observational or physical evidence of the astronomical data of the time of the Big Bang, there is much speculation amongst scientists as to the true perplexing nature of space and time at that time. Present computer models and speculations depict an environment where the universe was filled homogeneously and isotopically with comparatively very high energy densities and millions of degrees of temperatures and huge amounts of pressure in every corner of space and was rapidly cooling and expanding due to inflationary pressure.
In the first 0 to 10−43 seconds after the big bang and the expansion, also known as Planck epoch, is one of the most fundamental phases, in which one of the fundamental forces- the gravitational force, the weak nuclear force, the strong nuclear force and the electromagnetic forces, were unified as one and was a part of the Grand Unified force. At this time, the Universe was only to 1035 meters wide and therefore had a temperature of 1032 degrees Celsius. This was followed by the grand unification epoch beginning at 10−43 seconds, where gravitational force separated from the other forces as the Universe expanded and its temperature fell. Due to the enormous pressure and temperature of the Universe, it was too hot for the particles to be created and as a consequence, it was pre energy at this state.
At approximately 10−37 seconds after the expansion began, a phase transition called cosmic inflation occurred, resulting in an instantaneous increase in the expansion speed of the Universe, during which the Universe grew exponentially, much faster than the speed of light itself, and temperatures began dropping by a factor of 10,000. After approximately 10−36 seconds, the Electroweak epoch occurred during which the strong nuclear force separated from the other forces, while the other remaining electroweak force and weak nuclear force remained unified. Due to Cosmic Inflation, microscopic quantum fluctuations took hold and charge and were amplified by Heisenberg’s Uncertainty principle resulting in fluctuations that would later amplify into seeds forming the large-scale structure of the Universe.
After a period of 10−33 to 10−32 seconds, with the Universe expanding rapidly and its volume increased by a factor of 1078 . As temperatures fell and production of quark-gluon plasma started along with that of other elementary particles. But still due to enormous temperatures, even the random motion of particles were at the relativistic speeds. During these events, at some time, a mysterious reaction known as Baryogenesis violated the conservation law of Baryon number, resulting in a minute increase in the volume of quarks and leptons over antiquark and antileptons. It was approximately equal to 1 part in 30 million. This small anomaly magnified and resulted in the predominance of matter over antimatter in the present Universe.
Written By- Sukhjit Singh
He is pursuing B.Sc in Mathematics Honours from SGTB Khalsa College, Delhi University. He often takes up multiple exciting projects and aims to develop multiple skills.