Confused about the formation of "Stuff" in an Isotropic-ish Universe First let me state my current understanding so that I can be corrected if not on the right page-- Given "zooming out" far enough, our universe is rather homogenous/isotropic, but not perfectly so. If this is correct, I must admit my confusion and ignorance about the origin of "stuff" in our universe. (a stance perhaps ubiquitous to us all hah) My confusion is in that, although it makes sense to me that our universe should be slightly heterogeneous so that discrete entities can form (planets, stars, galaxies, etc.), I can't help but viewing any singularity described by the Big Bang as an entirely homogenous event. After all, in such case wouldn't it not make sense to talk about any individual particles or differing instances which would be capable of heterogeneity in that "primeval atom?" If so, I must wonder how such a homogenous event, which I would imagine should perfectly so and its expansion would also be perfectly even, could give rise to a slightly heterogeneous universe and thus stars, planets, etc. I've read of initial quantum fluctuations playing a prime role, but I am then confused as I must ask "Quantum fluctuations of what?"---of what parameters within the big bang singularity, of what entities? Perhaps then as well a many-worlds stylized interpretation alleviates the initial question, but I know there are cosmogonies (obviously) that do not support this line of thought and thus somehow reconcile the issues otherwise. Thanks for the reply, and hopefully I can understand the (likely) seemingly mind-breaking answers hah.