Origin Of The Universe [Breakdown By Seconds, Minutes And Hours]
Uncountable myths and theories have tried to explain the origin and fate of the universe, but there is one explanation which is widely accepted — The Big Bang Theory.
The Big Bang theory was a result of the observation that all other galaxies are moving away from our own at great speed in all directions as if an ancient explosive force had propelled them.
A Belgian priest named Georges Lemaître first suggested that the universe began from a single primordial atom. His idea instantly received a significant boost from Edwin Hubble’s observations that interpreted as showing that stars and galaxies are moving away from Earth in every direction. Fittingly, the velocities of recession increase in proportion with distance and this discovery has been confirmed by repeated measurements since Hubble’s time. These findings imply that the universe is expanding.
At the Big Bang itself, the universe is thought to have had zero size, and so to have been infinitely hot. But as the universe expanded, the temperature of the radiation decreased.
However, the radiation did not decrease immediately after the big bang. It took the universe years to cool down, and there is a timeline associated with it.
Let’s have a look at the timeline:
What happened 1 second after the Big Bang?
After one second, the temperature would have fallen to about ten thousand million degrees. This is about a thousand times the temperature at the centre of the Sun. Temperatures as high as these are reached in Hydrogen bomb explosions.
As the universe continued to expand, and the temperature to drop, the universe’s fundamental particles started to form. At this stage, it was still so hot that these particles hadn’t yet settled for the subatomic particles that we know today as neutrons, protons and electrons. Radiation at this time was so intense that colliding photons could form pairs of particles made of matter and antimatter. It’s thought that the early universe contained equal amounts of matter and antimatter.
Antimatter is defined as a material composed of the antiparticles of the corresponding particles of ordinary matter.
What happened 100 seconds after the Big Bang?
After a hundred seconds, the temperature would have fallen to one thousand million degrees, the temperature inside the hottest stars. At this temperature, the protons and neutrons would not have sufficient energy to escape the attraction of the strong nuclear force. They would have started to combine together to produce the nuclei of atoms of deuterium. The deuterium then would have combined with more protons and neutrons to make helium nuclei.
What happened 3 minutes after the Big Bang?
The protons and neutrons would have assembled into hydrogen and helium nuclei. By mass, hydrogen and helium were 75% and 25% of the early universe’s matter respectively.
What happened a few hours after the Big Bang?
After a few hours of the Big Bang, the production of helium and other elements would have stopped. After the next million years or so, the universe would have just continued expanding, without anything substantial happening. The regions which were slightly denser than average, would not have expanded as expected because of the dominance of gravitational force. This would have eventually caused to stop expansion and start to recollapse.
When the region got small enough, it would have started to spin very fast to balance the attraction of gravity. On the other hand, the regions which did not pick up a rotation would become oval-shaped objects called elliptical-galaxies.
As time went on, the matter would start to collect into clouds that began to condense and rotate, forming the predecessors of galaxies. Sufficient mass and the right forces would have caused the cloud to collapse after that, starting the nuclear reactions and birth of a star like our Sun. Stars more massive than our Sun would need to be hotter to balance their stronger gravitational attraction, making the nuclear reactions proceed much more rapidly.
Our Sun contains about 2% of the heavier elements from the early stages of the universe because it is a second-or third-generation star formed about five thousand million years ago out of a cloud of rotating gas containing the debris of earlier Supernovas. A small amount of the heavier elements collected together to form the bodies that now orbit the Sun as planets like the Earth.
How did life begin on Earth?
The Earth was initially very hot and without an atmosphere. Over a while, it cooled down and acquired an atmosphere from the emission of gases from rocks. The gases initially were not suitable to sustain human life and were poisonous, like hydrogen sulfide (the one with rotten eggs smell). However, other forms of life could have flourished under such conditions and would have originated in the oceans. The atoms would have combined to give rise to macromolecules, and they would thus have reproduced and multiplied.
The first primitive forms of life consumed various materials, like hydrogen sulfide and released oxygen. This further allowed the development of higher forms of life such as fishes, reptiles, mammals, and ultimately, the human race.
Wrapping It Up
Glossary
Friedmann: Alexander Friedmann was a Russian and Soviet physicist who derived the Big Bang model from Einstein’s equations.
Antimatter: Antimatter refers to sub-atomic particles that have properties opposite normal sub-atomic particles.
Deuterium: Deuterium is one of two stable isotopes of hydrogen. The nucleus of a deuterium atom, called a deuteron, contains one proton and one neutron.
Conclusion
I hope you got a ton of valuable information about the origin of the universe.
Now I’d like to hear what you have to say.
What is the most interesting point about the universe that you want to know more about?
Or maybe you are already aware of all this.
Let me know in the comments section below.
