The Big Bang

Origins One of the largest questions we can ask about the universe is, “How did it begin?” This question is not an easy one to answer, but data scientists have collected over many years may point us in the right direction Some of it is direct, while other bits are based on extrapolation

Hubble The big bang theory can be accredited to Edwin Hubble He discovered that the further away galaxies were from us, the faster they were moving away This implies that the universe is getting larger, and will be larger tomorrow than it is today This also works in reverse, meaning that it was smaller yesterday Taking this into account, scientists have calculated that the universe has been expanding for 13.8 billion years

Red Shift So how did Hubble observe the galaxies moving away from us? The answer lies in a phenomena that we observe here on Earth: The Doppler Shift (or Effect)

This is the observation that as an object moves towards you, the waves of sound are compressed closer together This would make the sound appear to have a higher pitch or frequency The opposite is true in that an object moving away appears to have a lower frequency Doppler Effect This works because of the wave-behavior of sound This also applies to light The only difference is that in light, frequency represents colour

Light from distant galaxies shifts to the red end of the light spectrum (low frequency) So, everything is moving away from us – expansion Into what, we aren’t quite sure

The Big Bang So, why the “big bang”? Based on their calculations, scientists hypothesize that the entire universe, matter and energy, had to be compressed into an unimaginably small point(singularity)…and then exploded outward It would have been incredibly hot and dense, and the forces that govern our universe would have combined into one Though it sounds crazy, we have seen similar conditions by colliding matter together at near-light speeds (Hadron Collider)

With every new collider we build, scientists get a clearer and clearer picture of what this early universe looked like This explosion must have some after-effects we can see today In 1964, two astronomers, Arno Penzias and Robert Wilson discovered that regardless of where they point a special telescope, they detected microwave radiation This was seen to be the “glow” left over from the big bang

The Future After the big bang, scientists could only determine one force acting on the galaxies – gravity Because of this, a “Big Crunch” idea was described where the universe would reach a maximum size, then collapse back on itself This was the foundation for Oscillating Theory The universe went through repeated periods of expansion and contraction, somewhat like a spring

What they found was the exact opposite – the universe is not slowing down in its expansion, it’s speeding up! So, what is pushing the universe apart?