It is wide accepted that the Universe as we know it began with the so-called "Big Bang"; however, we don't know what happened before that (if anything), so the Big Bang may not actually be the beginning.
big bang
The big bang began the expansion of spacetime with great rapidity. The Universe began with the Big Bang. In other words both space and time began at the big bang. The big bang started the Universe from the point t=0.
According to the big bang theory the universe began about?
big bang: This is the big bang theory
That is, more or less, the description of the Big Bang.
The Big Bang
Light is not the origin of the universe. The universe began with the Big Bang, a rapid expansion of space and time. Light is a form of electromagnetic radiation that was produced after the Big Bang as the universe cooled down and matter began to form.
The Big Bang theory suggests that the universe began as a singularity, a point of infinite density and temperature.
The matter present in the Universe began to become more and more dense and this huge density originates the big bang. That was the beginning of the Universe.
Why our Universe is composed almost entirely of matter, with almost no anti-matter in it.
The Big Bang
The Big Bang Theory.