Transcript: The big bang model has considerable predictive and explanatory power, but there’s some fundamental questions about the nature of our universe that it leaves unanswered. Why is the universe so smooth and isotropic? The reason this question is important to ask comes from a consideration of the early expansion. In the early big bang, regions of space were separating at larger than the velocity of light, yet the microwave background radiation shows an almost perfect black body or thermal spectrum. This can only occur when the entirety of space is in thermal equilibrium, and yet the superluminal expansion implies that there’s no way that light signals could have passed between different regions of space. So how did space come to a complete perfect temperature everywhere and throughout? Why is the universe so close to being flat? There is nothing about the standard big bang model that says that space should be utterly flat as opposed to curved. This becomes a mystery in the standard big bang model. Also, in the early universe there are many esoteric particles and defects of space time, and in the standard big bang model it’s a mystery as to why we do not see these, either topological defects or monopoles. None have been observed with telescopes or in particle physics detectors, and yet the big bang predicts that they should exist in space. Since we do not see these defects we need another explanation for their absence.