Philosopher Tim Maudlin is one of the top thinkers in the world on the subject of the nature and origin of the universe (i.e. cosmology). There's a six minute interview of him at Aeon in which he talks about some of the puzzling questions associated with the origin of the universe.
Specifically, he addresses the question whether something or nothing came "before" the Big Bang. Maudlin grants that if the universe is not eternal in the past it must have had a beginning. This raises the question, which he doesn't get into, of what caused the beginning since whatever comes into being must be brought into being by something else that already exists. If the beginning of the space-time universe is what we're trying to explain then whatever caused it must itself transcend space and time. Moreover, it must be exceedingly powerful and intelligent, and if intelligent then personal.
Furthermore, if we define the universe as the totality of contingent beings then the cause of this totality cannot itself be contingent (else it would be part of the universe) and must therefore be a necessary being. Necessary beings do not themselves have a beginning and thus do not require causes.
In other words, the cause of the universe sounds very much like the God of theism, but Maudlin, being a non-theist, doesn't draw out these implications. The interview is interesting but would've been much more so had he addressed the possibility that the universe is, in fact, the product of a creative act of God.
