At its simplest it talks about the universe as we know it starting with a small singularity then inflating over the.
Big bang theory earth science definition.
Different people use the term.
The big bang theory represents cosmologists best attempts to reconstruct the 14 billion year story of the universe based on the sliver of existence visible today.
Then between 10 billion to 20 billion years ago the exact timing is not.
In 1912 vesto slipher measured the first doppler shift of a spiral nebula spiral nebula is the obsolete term for spiral galaxies and soon discovered that almost all such nebulae were receding from earth.
The big bang theory is the leading explanation about how the universe began.
The big bang theory developed from observations of the structure of the universe and from theoretical considerations.
The big bang theory explains how the universe has evolved over last 13 8 billion years starting from a singularity to its current size.