It’s the cornerstone of cosmology, but what is it all about?

The Big Bang theory is a cosmological model of the observable universe from the earliest known periods through its subsequent large-scale evolution.

And Arno Penzias and Bob Wilson at the famous Bell labs observed exactly that in 1964, confirming the Big bang theory.

Each episode was reviewed by Dr. David Saltzberg, a physics professor at UCLA. What do you think? Here’s how physicists calculate g-2, the value that will determine whether the muon is giving us a sign of new physics.

4.) Scientists keep refining the theory of the universe, motivated by our observation of all the weird stuff out there. Lemaître's ideas, realized that if the Universe was expanding today, then the wavelength of the light in it was increasing over time, and therefore the Universe was cooling.

How long did all of this take? Since the early twentieth century, we have observed that far away galaxies are actually moving away from each other. The 1964 discovery of the leftover glow from the Big Bang was initially thought to be from bird poop. RELATED: The Big Bang Theory: Sheldon's 10 Biggest Mistakes (That We Can Learn From). , time, and all matter originated from a singular point, which then expanded incredibly quickly to form the quark-gluon soup. But there's a suite of observations -- led by the fluctuations in the primeval fireball -- that teach us there was a different state prior to that, where all the energy in the Universe was inherent to space itself, and that space expanded at an exponential rate.

Because it got so big and led to such great things, some people call it the "Big Bang."

red box indicates the extent of Hubble's original data.

Fred Hoyle, a proponent of the Steady-State Theory, was making a different prediction where he believed the universe continues forever without a beginning. If you extrapolate this thinking, all matter was once so close together it formed what scientists call, the singularity. This can allow the jellyfish to live on forever.

This Big Bang theory had predicted the occurrence of background radiation. Image credit: Robert P. Kirshner, PNAS, via Not only are we made of fundamental particles, we also produce them and are constantly bombarded by them throughout the day.

This hypothesis is called the chaotic inflation theory. One of the first scientists who formulated the theory was a Catholic priest.

Both were the Steady States theory and Big Bang Theory.