The most widely accepted theory of the origin of the universe states that there was a mass expansion trigged by quantem flutuations in what is mathematically modeled as a single point of gravitational singularity. Our current understanding of relativity projects it as an infinitesimally small "place" of infinite temperature and density, not bound by the laws of space or time. The exact nature of the singularity is however still a somewhat unsolved mystery of cosmology. What happened next is more certain. A period of "cosmic inflation," where in a fraction of a second there was a mass expansion of space itself, faster than light, after the expansion slows, we are left with a sea of only the most fundamental partials in existence, such as quarks and electrons. As the universe cools the quarks start to form into protons and neutrons, bound by the strong nuclear force facilitated by particles known as gluons. Protons formed by two up quarks (each with a positive charge two-thirds of the elementary charge) and one down quark, (with the negative charge of one third that of the elementary charge) making the particle positively charged. Neutrons having the opposite arrangement, two down quarks and one up, making them have no charge. As the cooling continued these particles bound together making the first atomic nuclei, and over hundreds of thousands of years, spaced cooled enough for electrons to begin to orbit these nuclei, creating the first true atoms. The exact process by which this happened remains something of a mystery, but these insights can be gained by studying the cosmic background radiation leftover.
