I'm familiar with the Horizon Problem and how it is solved by the theory of Inflation. I also know that Inflation solves some other cosmological problems and fits well with the current CMB data. Just focusing on the Horizon Problem, however, I'm curious about one thing. It seems to me that one solution to the Horizon Problem is to assert that whatever first created the universe did so with complete homogeneity, without the need for different parts of the universe to interact and become uniform. Imagine, for example, that the universe was created at time t=0 with a size of one light year, and with complete homogeneity, because the process of creation required a specific energy density with extreme precision. I'm not suggesting that this is a valid theory, I'm just curious as to what leads us to reject this hypothesis. As far as I know, no one has a conclusive answer as to what process actually created the universe - how do we know it didn't require homogeneity?