The Birth of The Early Universe

Travel back to the Universe’s first moments and discover how energy became particles, antimatter vanished, atoms formed, and light finally escaped through space. This beginner-friendly journey explains the early cosmos using simple analogies, and examples.

Introduction

In the previous blog we understood the Big Bang in the simplest form with the help of real life analogies and examples and I really hope you had got the idea how this theory proposes the beginning of our Universe. So what next? yes… you got it right what happened right after the big bang? how come the particles such atoms came into existence and what was the state of our Universe in the very beginning. These questions would be in your mind and I will talking about these topics,. so lets begin.

The Planck Era

The earliest time after the Big Bang that can be properly described is 10^-43 seconds, before this all our physics breaks down and this Time is called the PLANCK TIME. Remember this is time before the cosmic inflation, that means our universe was still in that unimaginably hot dense state and temperature was around 10^32 kelvin. At this time Scientists think that the four fundamental forces namely, Gravity, Electromagnetism, Strong Nuclear Force and Weak Nuclear force were united into a single force. But the question arises how and why. Scientists noticed that at extremely high energies these forces start behaving more and more similar in the mathematical equations and experiments.

Now something very strange happens, the universe started expanding enormously around 10^-36 to 10^-32 seconds*(Imagine universe expanded from the size of atom to the size of a in just a fraction of time and really we dont know why)* known as the cosmic inflation. you guys already know that I explained this topic already in the previous blog so we will move ahead to the next topic.

Energy Turns Into Energy

After the inflation, the Universe was still very hot but now it was the time when energy becomes matter. So I think most of us know the famous equation, E=MC^2

This equation describes that pure energy transformed into particles. So the particles and antiparticles started to form and these included quarks, electrons, neutrinos, photons but the temperature was so high that particles collided violently and atoms could not exist. Also Scientists think that in the early Universe Matter and Anti-matter were in almost equal amounts but not perfectly equal. But what is anti matter?

OK…. so let me define it in easy terms, Antimatter is liken the mirror version of matter. Every matter particle has an antimatter partner with same mass but opposite charge.

the important thing here is that when matter and antimatter touch they destroy each other and back to energy and this is called annihilation.

but somehow a tiny excess of matter survived otherwise if they had been perfectly equal then Universe wouldn’t contain any matter toady. nothing no stars, no planets.

Formation of Protrons and Neutrons

About 10^-6 seconds, the Universe cooled enough for Quarks to combine. Three quarks joined to form: Protons and Neutrons and these are the building blocks of the Atomic Nuclei. Before this the Quarks moved in a superhot plasma. But you may ask what is the superhot plasma? let me explain it to using an analogy:

Imagine putting ice in a pan and heating it, the ice melts into water and on further heating the water turns into steam. Now if we go on heating the steam, the atoms become intensely hot and its subatomic particles start drifting away and everything becomes glowing, chaotic soup of particles. this is known as the Superhot plasma and these quarks were also dancing around in this soup before combing.

The First Atomic Nuclei Forms

Around 3 minutes, the universe cooled to about a billion kelvin. Now Protons and Neutrons could stick together. This process is called Big Bang Nucleosynthesis, it mostly produced Hydrogen Nuclei, helium nuclei, tiny traces of lithium but still they were no complete atoms they weren’t complete atoms because the electrons were missing. But why the electrons couldn’t stay with the nuclei? its because they were too energetic, so the Universe was somewhat like a glowing ionized plasma.

Formation of Atoms

After 380,000 years later…oh! what that is so long, we were in the earliest times, why we skipped this much of time.. because there was nothing special during this time.

Now the Universe has cooled to around 3000 kelvin and finally now after around this much of time the electrons slowed enough to attach to the Nuclei. This created first the neutral atoms mostly hydrogen atoms and helium atoms. so the first atom formed from protons, neutrons and electrons.

The Light

Where did light came from? In the early universe as you know there was the matter and the antimatter which collided with each other and produced a type of energy called as the light and light was produced in the form of photons(Photons are massless small packets of light energy). However before the formation of the first atoms the light couldn’t move freely, the particles scattered these photons and then after 380000 years when the atoms formed, photons could move freely. The thing is that this ancient light still exists today as the Cosmic Microwave Background and I will cover it in more detail in the upcoming blogs.

Conclusion

In this blog, we covered a lot things, the state of the universe after big bang, formation of particles, then atoms etc. Was this the end? No this is just the beginning of the cosmic journey. After this blog I will cover how the stars formed, CMB and many things. I really hope that you got the idea of how the early Universe looked like. I will meet you in the next blog, till then bye.