The big bang theory is the popular explanation for where the galaxies, stars, planets and people came from. Those who believe in the big bang acknowledge that there are questions that need answering, such as where all the material that makes up the universe came from and what made the universe expand.
Before the Big Bang
According to the scientific community, all the matter in the universe, as we know it today, began in a very tiny, hot and compacted point.
Bang
At the moment of the big bang, the point began expanding like a balloon, versus the long-held misconception of an actual explosion. As the point of matter expands, which it continues to do today, it cools, contracts and forms stars and galaxies.
Inside
Before the big bang, nothing existed, not even space. Space and time, according to scientists like Steven Hawking, George Ellis and Roger Penrose, were created after the big bang. The three scientists performed mathematical calculations to help prove their ideas in the 1960s and 1970s.
Evidence
Galaxies observed from ground-based and space telescopes confirm that galaxies are moving away from the Earth. Also, telescopes with the ability to measure radiation in space detect residual radiation throughout space, which indicates that something massive occurred.
Theory
The big bang theory remains a theory because the evidence available only traces what we can see from our place in the universe back through time, which could be incomplete. In addition, those who believe in God will not accept that the universe sprang from nothing and for no reason.