Big Bang Theory

Throughout our lives, we've lived on a planet that was conceived long before we were born. It is easy to take the timeline of the Earth before life for granted because we have little to no biological records or experiences of it. While there is extensive geological history telling us about our planet, that history still doesn't let us conceptualize our full beginning. What came before Earth? The Sun was formed through a likely molecular cloud which gave rise to a protoplanetary disk that created our planet. However, we can keep asking ourselves this question. What came before that molecular cloud? What came before that, so on and so forth. Eventually, we have to reach a starting point. Our observable universe had to start from something.

That something is what cosmologists, people who study the universe as a whole, call "the Big Bang". You've probably heard of the Big Bang before, through its numerous references in popular culture. Well, what is the Big Bang exactly? This unit aims to simplify the Big Bang and what it did. The topics for this unit are the stages of the Big Bang evolution chronologically. However, it won't go over the entire history of the universe. It will simply cover up until large-scale universal structures like stars start to form. After stars form, the stellar evolution cycle can be read up on to analyze their evolutions.