Big Bang Theory

"When nothing exploded and created everything."

It is believed that the entire universe as we know it started about 15 000 million years ago.  All matter was concentrated into one point called a singularity, where conditions were so extreme that the normal laws of physics did not apply.  Originally the term "Big Bang" was coined on a radio broadcast by the then Astronomer Royal, Sir Fred Hoyle, who was scathing about the theory.

However there is a wealth of evidence that the universe started from a single event, which physicists are starting to understand in increasing detail.

Surprisingly, to understand what was a huge event, we need to turn to the very small.  You will see these words applied to the observations:

• Macroscopic - things that happen on a big scale;
• Microscopic - things that happen on a small scale, at the level of the atom.

We will explore in this unit microscopic phenomena like:

• atoms, nuclei, and electrons;
• fundamental particles;
• fundamental force.

In other words we will get right down to the nitty-gritty of matter, then we will look at how it can inform us about the big bang, and what happened immediately in its aftermath.