Nat Geo Origins of the Universe

Big Bang Theory

Most widely accepted explanation for the origin of the universe

What the universe was like at the begining

A hot and infinitely dense point

How big was the universe before the big bang?

only a few millimetres wide, it was similar to a supercharged black hole

How many years since the big bang?

13.7 billion

What was created from the big bang?

all matter, energy, space, and time

Did the Universe explode or expand?

Expand

Two major stages of the universe’s evolution

Radiation era and matter era

Radiation era epochs

Planck, Grand Unified Theory (GUT), Inflationary, Electroweak, Quark, Hadron, Lepton, Nuclear

Planck epoch

Immediately after the big bang

Matter did not exist

Energy existed

gravity split away from the superforce at the end of this era

Grand Unified Theory epoch

this epoch ended when the strong nuclear force broke away from the superforce

Inflationary epoch

The universe rapidly expanded

It was hot

Electroweak epoch

The final two forces split off : electromagnetic and weak

Quark epoch

Subatomic particles could not form because it was too hot

Hadron epoch

Quarks bound together to form protons and neutrons

Lepton epoch

Protons and neutrons fused and created nuclei

Nuclear epoch

First chemical element create: helium

Q: What were the four components of the original superforce?

Gravity

Strong Nuclear

Weak

Electromagnetic

The Matter Era definition

the presence and predominance

of matter in the universe

The Matter era epochs

Atomic, Galactic, Stellar

Atomic epoch

The universe’s temp cooled down enough for electrons to attach to nuclei for the first time. Called recombination, this process helped create the universe's second element, hydrogen.

Galactic epoch

Hydrogen and helium gas now clustered to form atomic clouds. Small pockets of gas may have had enough gravity to cause atoms to form clusters of atoms, which became the seedlings of galaxies.

Stellar epoch

Stars began to form in those galaxies. All of the elements on the periodic table were then created in the hearts of those stars, forming the building blocks of everything.

What was the first element created?

Helium (He)

In what epoch did the cooling trend of the universe get disrupted, and why?

Lepton epoch, The fusion of protons and neutrons to create nuclei released energy.

In what order did the forces split away from the superforce? (Strong Nuclear, Electromagnetic, Gravity, Weak )

1. Gravity

2. Strong nuclear

3. electromagnetic and weak nuclear