In his previous book, A Brief History of Time, Hawking had appeared to accept the possibility of a creator, saying the discovery of a complete theory would allow humans to 'know the mind of God.' (Canadian Press)

Physicist Stephen Hawking says God wasn't necessary for the creation of the universe.

In his new book, The Grand Design, the British scientist says unravelling a complex series of theories will explain the universe.

The book, written with Leonard Mlodinow, is to be published Sept. 9.

In an extract published in the Times on Thursday, Hawking says spontaneous creation is the reason there is something — as opposed to nothing.

Hawking says "it is not necessary to invoke God to ... get the universe going."

In his previous book, A Brief History of Time, Hawking had appeared to accept the possibility of a creator, saying the discovery of a complete theory would allow humans to "know the mind of God."