by- Aman Raj
Introduction
Common folks are familiar with the Big Bang Theory, that is the best-known solution we have in regards to the start/origin of the Universe. What people aren’t aware of are the things that took place just after the Big Bang. This blog will introduce you to the facts and speculations about the Universe in its infancy.
About
The Big Bang
When there was no matter or disturbance in the space, but only a single hyper-sphere which we call a singularity as we are unable to research on that topic, the Universe was supposed to be at temperature 0 Kelvin. In this giant object, there was a sudden energy spark that created a small disturbance. It didn’t take this disturbance much time to spread all over like a domino effect and there was a threshold to which these disturbances could be contained, as a result of crossing the threshold the giant object blasted. This is called Big Bang, from the point where there was an energy spark to the object blowing up.
Universe after T+0 seconds
One can even say that time for Universe only started after the blast itself. So, there was high uncertainty among particles such as electrons, positrons, neutrinos, protons, neutrons, etc. as they were moving with very high velocities. When the Universe was one second to three minutes old, considering the motion of particles and the temperature at that moment led to the formation of nuclei. To match the circumstances of moving particles just after the Big Bang, researchers developed particle accelerators. A particle accelerator, as the name suggests, accelerates a particle to very high velocity and lets the researchers observe its behavior. The velocity that humans have achieved is not enough to make it look comparable to the actual speed possessed by particles after the Big Bang. This doesn’t mean there is no certain proof of Ancient Cosmic Makeover. If the theoretical results are on par with the experimental results, for the time being, it can be considered successful.
Grand Unified Theory
In physics, one has often heard of the four fundamental forces of nature i.e. the gravitational force, the force due to electromagnetism, the weak nuclear force (behind the decay of neutron), and the strong nuclear forces (binds atomic nucleus). It was in the mid-nineteenth century when James Clerk Maxwell unified forces of electricity and magnetism, later on, weak nuclear forces were unified with electromagnetic forces to form electro-weak theory. Many researchers came up with the idea of combining the strong nuclear force with electro-weak theory. that was named Grand Unified Theory (GUT). Much later, astronomers are trying to unify gravitational forces with the other three forces. Much to everyone’s surprise gravitational force is a very weak force by nature and to unify it with other fundamental forces researchers need to achieve the energy level of $10^{16}$GeV in the particle accelerator. However, the best accelerator built can let us research at the energy level of $10^{3}$GeV.
Role of the GUT in the Early Universe
As we have learned in the previous paragraph GUT needs the energy of the order 10¹⁶ GeV, which is only possible to achieve when the Universe is in its early stages. However, when the GUT began gaining everyone’s attention, people found faults in this theory with a very huge fault margin. Three problems arose namely, the horizon problem, the flatness problem, and the monopole problem. Later in the 1970s, a solution was proposed to counter the three problems which we call the inflation of the Universe. Many folks often confuse inflation of the Universe with the expansion of the Universe, which is true when we talk in terms of language but much different when we apply mathematics. Normal expansion means that an object will expand at a predefined rate, consider simple interest. Whereas, Inflation of the Universe means that Universe will expand based on an iterative phenomenon i.e. the expansion rate will be contemplated based on the previous state of the Universe. Thus, inflation of the universe has taken place because of the energy released during phase transition. And, phase transition was the result of GUT interaction among particles.
Conclusion
Readers keep in mind that theories such as GUT or inflation are not tested and these are just theoretical explanations for an early universe, when we have potential resources and knowledge to experimentally verify these theories then they may turn out to be true or may not be true. But this is the beauty of science, if humans are on a wrong track and after years we make a breakthrough that contradicts our past innovations and discoveries, then there is no reason to feel sorrow. Although we were in the wrong initially we study those failures and that helps us think from the perspective of others. Here’s an example: for years scientists have studied various wrong models of the structure of an atom, and we are still not fully sure if we are still wrong about the current model, but this also makes it very interesting to know how people were studying the wrong model of an atom still they came up with brilliant ideas to prove that the particular model of an atom is accurate. Someone has quoted, ‘The doing is often more important than the outcome’.
