Threshold 1: The Big Bang
About this video
The Big Bang, about 13.7 billion years ago, is the first threshold of increasing complexity. We know little about what came before it, but we do know it produced space, time, matter and energy, which soon separated into forces like gravity and particles like quarks and electrons.
You'll be able to
- explain why the Big Bang is called the first threshold.
- describe what existed just after the Big Bang: space, time, matter and energy.
- explain why scientists can only speculate about what came before the Big Bang.
Key words
- threshold
- A turning point when something new and more complex appears in the history of the Universe.
- Big Bang
- The event about 13.7 billion years ago that created the Universe.
- Goldilocks conditions
- The 'just right' conditions needed for something new to form.
- quarks
- Tiny particles of matter that linked up to form protons and neutrons.
- electromagnetism
- One of the forms energy took after the Big Bang, alongside gravity.
Transcript
NARRATOR: Our first threshold is the Big Bang, which happened about 13.7 billion years ago and led to the creation of the entire Universe. We don't know much about the ingredients and the Goldilocks conditions that led to this first threshold because we just don't have much evidence.
For example, what made the Big Bang possible? We don't know. Why did the Big Bang happen? We can only speculate. Was there even space and time before the Big Bang? We don't know that either. What we do know is that the Big Bang provided the raw materials for everything around us today.
After the Big Bang there was space, which was rapidly expanding, and there was time. There was also matter and energy. At first, the Universe was so hot that you couldn't tell the difference between matter and energy, but within the first billionth of a second after the Big Bang, matter and energy separated.
Then energy took different forms, including gravity and electromagnetism. And matter appeared in the form of electrons and quarks. And quarks soon linked up to form protons and neutrons. Why is this so important? Because nothing had turned into something, and that something contained everything needed to build an interesting Universe, one that could eventually include you and me.
Now let's take a closer look at how our Universe began to build more complex things.
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