The Big Bang Theory is a cosmological concept of the observed universe and its subsequent large scale evolution from the earliest known times. The model explains how the universe evolved from an initial state of intense high density and high temperature, which gives a detailed explanation for a vast variety of observable observations including the concentration of light particles, cosmic microwave background (CMB) radiation, which large-scale structure.
The universe cooled enough after its initial expansion to allow for the creation of subatomic particles, and later atoms. Giant clouds of these primordial elements-mainly hydrogen, with some helium and lithium-gradually coalesced through gravity, creating early stars and galaxies whose descendants are visible today. Astronomers observe the gravitational influence of an unseen black mass surrounding galaxies, in addition to these primordial building blocks.
The Big Bang is a theory explaining our Universe’s expansion from a point of origin around 13.8 billion years ago.
This imaginary starting point of everything was an eternal accumulation of material, called the singularity. Do not fear, if you find this difficult to imagine. Don’t be afraid. Atomic rules don’t accommodate infinite quantities well, meaning things like space, time, and a lot of various powers don’t mean much in this tiny ‘pot’ from which the World has arisen.
This amount of energy was so intense science can’t yet offer a simple explanation of what was going on for the first 10-43 seconds of expansion.
Since the Big Bang, the explosion ‘jumped’ around 10-35 seconds, allowing the World to expand in size in a simulated moment by a multiple of about 1050. This time of ‘inflation’ helps understand why the natural radiation from the Universe appears as smooth as it does.