Explain The Evidence That Support The Big Bang Theory

AS:91415

Title: The Big Bang - what’s the evidence?

The big bang, is the current widely accepted theory that explains how the universe came to exist as it does today. However the big bang wasn’t always the accepted theory in the scientific community to describe how our universe formed.

The current major pieces of evidence that support the big bang theory are.

Redshift:The universe is expanding.

CMBR:cosmic microwave background radiation, energy released shortly after the big bang

Observing distant stars:Inspecting the elemental composition in these ancient stars.

Redshift occurs when galaxies move further away from us, and is observable by a red-shift of light from distant galaxies, this red tint is created by the doppler effect where

The CMBR is leftover from a dense and intensely hot period early in the universe known as the recombination era where the universe was so hot protons and electrons couldn’t combine and instead formed a plasma, when the universe cooled down below 5000 degrees fahrenheit these protons and electrons could recombine, this recombination released photons which are now form the CMBR we can observe today. The CMBR was key in the big bangs surge in popularity, as it was locked in a debate between itself and the steady state theory, a theory where the universe is perfectly universally dense and the universe creates matter as it expands, this theory expects the universe to be infinitely old. With the CMBR showing that the universe wasn’t constant and was much denser and hotter, lending credence to the big bang and pushing the steady state theory into the shade as the much denser universe that is seen from the CMBR is antagonistic to the universe being perfectly constant and infinitely

The farther away we look with telescopes on earth, the longer back in time we are looking. This is because the light from distant stars takes millions or billions of years to reach us on earth, giving us a view of ancient stars, billions of years before the earth was formed. And allows us to observe the chemical composition of those stars. Many of these stars that were found show signs of very small amounts of heavy metals in comparison to relatively new stars such as our own “If you could compress all the iron in the Sun to the size of your fist, some of these stars would contain just a tiny pebble by comparison,"-Dr Andrew Casey

These low amounts of heavy elements in these early stars supports the big bang theory, as it shows that there were much much less amounts of heavy elements earlier in the universe than there are now, compared to the steady state theory in which the universe should have had a constant ratio of heavy elements at any time.

The other theories that competed with the big bang

The steady state theory: The steady state theory was a cosmological model that was in competition with the big bang, the steady state theory hypothesized that the universe created mass as it expanded, resulting in the universe having constant mass. Also the steady state theory states that the universe would be infinitely old, with no defined