Most of the discussions at this forum are way beyond my level of understanding, but I thought this might be a good place to start. My background is just a college level knowledge of physics, and a hobbyist's interest in astronomy. My question involves the mass of the universe, and a description of a singularity. It is my understanding that the visible universe consists of approximately 125 billion galaxies, averaging approximately 100 billion stars each. It's also my understanding that this amount of matter comprises at most, 10% of the total mass of the universe. What totally amazes and bewilders me, is how a mass of this enormity can have been so infinitely compressed into a point singularity that was then the object of the Big Bang explosion. How did all this matter exist in the same place at the same time? Is space and time no longer relevant here? Any help in understanding this (in layman's language please :-) would be greatly appreciated. p.s. please excuse or correct any misstatements I may have made, but I think the gist of the question is clear.