There is no scientific indication of what set the whole process in motion ;-)

In essence, I know people who consider evolution so elegent a mechanism that they feel it reasonable to consider it designed. Once in motion, they don't see the hand of a deity in it. But as a process, they see it as the method by which a deity can turn the switch and let life go. I don't personally feel that way, but I understand it and it really is more reasonable an approach than putting science in opposition to religion. Someone who reconciles the two holds faith but recognizes that science is really telling us the way things are and is, in essence, a window into how god works. Someone who discounts science when it contradicts their faith essentially must believe that god plays nasty tricks on people.

More broadly, since the laws of physics break down at the moment of the big bang, it is hard to see how there ever COULD be a scientific explanation for the very beginning of the universe. Science breaks down and any experiment to test the conditions at that momen would by definition require the entire energy contained in the universe. So, hypothesizing a bearded old man fliping a light switch and saying, "Let there be light" is as reasonable as any other hypothesis. By that I mean it is just as provable.