The Big Bang- 2

Have you ever thought where all these atoms which are the building blocks of almost everything come from? All these are results of the Big Bang: the left over excess matter after the antimatter (positrons/ anti protons)and the matter annihilated. This is what happens when matter and anti matter particles collide on to each other.

The result of the annihilation of the electron and positron creates gamma ray photons or at higher energies other particles:

e⁻ + e⁺ → γ

During a low-energy collision, proton-anti proton annihilation usually produces a collection of pions or related light mesons. High-energy particle colliders, like the tevtrons, sometimes collide protons with anti protons at very high energy and these collisions can produce a long list of heavy particles.

(Source- Wikipedia)

At this stage the universe was 0.7 billion years old and consisted of subatomic particles smashing into each other due to the high temperature the universe held. Then as time passed by the expanding cosmos cooled sufficiently enough for the protons and the neutrons to bind together with the help of the nuclear forces to form the first atomic nuclei H and He.

p +n → ²H⁺ nucleus (deuterium)

2p +2n → ⁴He²⁺ nucleus (alpha particle)

But still there weren’t proper atoms with missing electrons because the heat and the energy of the hot baby universe provided the electrons great amount of kinetic energy that it could not exist stably bonded to the nuclei. It took nearly 3.8 million years after the big bang to reach the temperature suitable to the creation of complete atoms. From the beginning the universe was in total darkness where light was trapped inside a thick fog of fast moving electrons. The drop down in temperature reduced the energy of the electrons and slowed them down, finally ready be bonded to create the firet atoms. This was called the Big Bang nucleosynthesis. As the dense fog was reduced with the decreasing number of unbound electrons light was released. Overtime this burst of light dimmed and cooled losing energy to become microwaves. This faint microwave radiation was picked up by Prof. Arno Penzias and Robert Wilson in 1963 which marked the critical moment of origin of the first atoms.

But the world we live in nowadays consist of more than 100 elements. Without the other elements there’s no chance for us to exist, not even planets and galaxies. To form the others the H and the He atoms had to fuse together somehow. But how exactly? To do this stars came in to picture.

See you in the next post with stars.