Big bang explaination

1. BIG BANG THEORY
Nipin K P
kp.nipin@gmail.com

2. Origin of Big bang Theory
• A Belgian priest named Georges Lemaître first suggested the big bang theory in
the 1920s when he theorized that the universe began from a single primordial
atom. The idea subsequently received major boosts by Edwin Hubble's
observations that galaxies are speeding away from us in all directions, and from
the discovery of cosmic microwave radiation by Arno Penzias and Robert
Wilson.

3. Big bang Theory
• It is the prevailing cosmological model that described the early development of the
universe.
• This theory is consistent with observation of the past and the present state of the
universe and is widely accepted within the scientific community.
• According to this theory, universe had started from a single point and the big bang
occurred approximately 13.8 billion years ago, which is thus considered the age of
universe.
• At this time the Universe in an extremely hot and dense state and began
expanding rapidly.

4. • After the initial expansion, the universe Cooled sufficiently to allow energy to be
converted in to various subatomic particles, including protons, neutrons and
electrons.
• Though simple atomic nuclei could have formed quickly, thousands of years were
needed before the appearance of the first electrically neutral atoms.
• The first element produced was hydrogen along with traces of helium and lithium.
• Giant clouds of these primordial elements later coalesced through gravity to form
stars and galaxies. And the heavier elements were synthesized either within the
stars or within the supernovas.
• The universe has no borders it still continues to expand and expand from all
around it is just nothing.

5. Figure: The big bang. The universe began 13.77 billion years ago with a sudden expansion of space, matter, and energy, and it
continues to expand today. [Source: KP, modified after NASA/ WMAP Science Team, http://bit.ly/BBdiagram]

6. The Big Bang Theory- Proof
• Galaxies appear to be moving away from us at speeds proportional to their
distance. This is called "Hubble's Law," named after Edwin Hubble (1889-1953)
who discovered this phenomenon in 1929. This observation supports the
expansion of the universe and suggests that the universe was once compacted.
• If the universe was initially very hot, as the Big Bang suggests, we should be able
to find some remnant of this heat. The universe is filled with such radiation that is
left-over from the Big Bang called Cosmic Microwave Background Radiation,
which was discovered by radio astronomers Arno Penzias and Robert Wilson in
1965.

7. • Finally, the abundance of the “light elements” Hydrogen and Helium found in the
observable universe are thought to support the Big Bang model of origins.

8. Common Misconceptions
• People often tend to think of a giant explosion, when really the Big Bang was and
continues to be an expansion. Instead of thinking of it as a balloon popping;
imagine it as a balloon expanding and filling with air continuing on and on to the
size of our universe.