In this case the title does not refer to the great nerd TV series but the actual Big Bang theory, something every nerd wished they could explore and explain: The Origin of the Universe.
From the Youtube page:

We made this video about the Big Bang because the theory is important and amazing, but often misunderstood.
This video was produced without any funding from any outside sources. It was put together with donated creative time from a group with a desire to further public cognition of science.
Science has many amazing stories to tell, this is the first. The Big Bang Briefly.