[Geko45]

Yes, science has a theory as to what caused the Big Bang and the theory makes predictions that should be observable and testable still today. So, I don't want to hear theists claim that "scientists have no idea what came before the Big Bang" anymore. If you want to challenge the validity of the theory, here it is complete with all the supporting math. Break out your slide rule and microwave detector and have at it.

The Ekpyrotic Universe: Colliding Branes and the Origin of the Hot Big Bang - Justin Khoury (Princeton), Burt A. Ovrut (Univ of Pennsylvania), Paul J. Steinhardt (Princeton), Neil Turok (Cambridge)

We propose a cosmological scenario in which the hot big bang universe is produced by the collision of a brane in the bulk space with a bounding orbifold plane, beginning from an otherwise cold, vacuous, static universe. The model addresses the cosmological horizon, flatness and monopole problems and generates a nearly scale-invariant spectrum of density perturbations without invoking superluminal expansion (inflation). The scenario relies, instead, on physical phenomena that arise naturally in theories based on extra dimensions and branes. As an example, we present our scenario predominantly within the context of heterotic M-theory. A prediction that distinguishes this scenario from standard inflationary cosmology is a strongly blue gravitational wave spectrum, which has consequences for microwave background polarization experiments and gravitational wave detectors.