Origin of the Universe - The Big Bang Theory, Evolution and Timeline of the Universe

The video explains How the universe was created. This documentary is based on Origin and evolution of the universe. You will know how the universe came into existence 13.7 billion years ago after the big bang and before the big bang our universe was just a singularity but within fractions of a second the universe grew tremendously.

This all has been explained in the video as timeline of the universe from its beginning to the present time. There was no time or space before 13.7 billion years ago. Suddenly NOTHING changed into EVERYTHING.

The BIG BANG

The universe came into existence with Big bang around 13.7 billion years ago. Actually nothing existed before the big bang not even the time. Contrary to common belief, big bang was not really an explosion. In big bang the space itself expanded. The Big Bang model states that before the big bang, the whole universe was in the form of a point of infinitely small size, infinite density and also infinitely high temperature. This is called as the Singularity.

Origin of the Universe Video

Cosmic Inflation Era

Within first millionth of a trillionth of a trillionth of a second after the big bang, the universe grew really big!!! There was an exponential expansion of the universe in this extremely small span of time. This inflation era lasted from 10^-36 seconds to around 10^-32 seconds only. Therefore this phase of the universe is known as the Cosmic Inflation era.

Formation of the First Atoms

A few milliseconds after the big Bang the temperature of the universe was about 5 trillion degrees Celsius. At this level of temperature elementary particles like Quarks and Gluons mixed up to form a soupy primordial fluid that spread throughout the cosmos. Protons and neutrons are made up of Quarks and...Gluons act like glue to combine Quarks together so that protons and neutrons can be formed. When the universe was just 3 minutes old, Protons and neutrons fused together. This fusion process formed an isotope of hydrogen called as deuterium and also helium. But this process stopped as the temperature decreased. Finally after 380 thousands years after the big bang the temperature dropped to a level that was suitable for hydrogen and helium to combine with free electrons and in this way first neutral atom came into existence.

The Dark Ages

This was a very long duration of time that lasted nearly 100 million years, when there was no source of light in the universe. Therefore we call it The Cosmic Dark Ages. As most of the knowledge about the universe is obtained almost entirely from the light of stars, this makes it very difficult to get insight into this phase of the universe where stars were yet to form.

Formation of Stars

After the long dark ages, formation of stars started in the universe. This phase started by around 180 million years after the big Bang and continued for around 500 million years after the beginning of the universe. Because of gravitational force clouds of gases were pulled together and formed large sized spherical structures. At high enough temperature and pressure in the core of the spherical shapes, fusion reactions were triggered. In the fusion reaction two atoms of hydrogen fused together to form a single atom of helium. The fusion reactions in the stars generated large amounts of energy that lit up the universe. With the passage of time our universe filled with such shining stars. This stage in the evolution of the universe is known as the 'Cosmic Dawn' or 'reionization'.

Merging of Galaxies and Formation of Black Holes

Large sized galaxies started to form by the merger of smaller galaxies. Nearly 1 billion years after the big bang, supermassive black holes formed at the centers of the galaxies. Galaxies also grouped together due to attractive force of gravity and formed galactic clusters containing hundreds to thousands of galaxies. The brightest things in the universe was also formed called as Quasars. In this way the universe continued to evolve for billions of years.

Birth of the Solar System

Nearly 4.5 billion years ago clouds of gases collapsed down in a galaxy known as the Milky way. In this galaxy formation of a medium sized yellow star (Sun) took place under the influence of attractive force of gravitation. The star having 9 rings around it coalesced into 9 planets. The 3rd planet from the Sun was at the right distance from it that provided suitable conditions for the life to flourish. That planet was our home planet, the earth. Here on our planet different types of life forms evolved ranging from microbes and tiny creatures to gigantic Dinosaurs. As time passes various other species of plants and animals also appeared on the planet. And finally about 200 thousands years ago from the present time, the most intelligent life...humans evolved on earth. So this was the journey of our universe from its beginning to the present time. Credits and Source: https://www.livescience.com/65471-photo-timeline-big-bang.html