Then between 10 billion to 20 billion years ago the exact timing is not.
Big bang theory earth science definition.
The big bang theory is the leading explanation about how the universe began.
The big bang is how astronomers explain the way the universe began.
The big bang theory explains how the universe has evolved over last 13 8 billion years starting from a singularity to its current size.
The big bang theory tells us that the entire universe was once condensed in the form of a primeval atom or a dense mass.
At its simplest it talks about the universe as we know it starting with a small singularity then inflating over the.
Different people use the term.
It is the idea that the universe began as just a single point then expanded and stretched to grow as large as it is right now and it could still be stretching.