Big Bang - Start of our Universe

What is the Big Bang theory for the creation of the universe? In principle it is as easy as saying there was a large explosion of unimaginably hot energy, which 'cooled' to form the fundamental particles and forces that we see in the universe today. This happened about 13.7 billion years ago, according to present-day best measurements and calculations.

As with any scientific theory, no one should put any belief into it until there are predictions made from the theory that are then tested experimentally and through physical observations. Over the past 100 years, the theories of Einstein and the eventual Big Bang models have gone through this slow process, and confirmation of the key ideas have occurred, making this the best understanding we have for the universe's creation.

Check out this video that explains the gist of the Big Bang theory, and a couple reasons why scientists believe it is a valid theory. Check here for a quick example of the Doppler effect.