The universe, of which our domicile the planet Earth forms but a minuscule part, has an architecture that changes and has been changing in time. In other words, it has a history of evolution. Lack of experimental evidence denies us the knowledge of what the universe was like “at the time of its origin,” as discussed by Hubert Reeves in the preceding chapter. Neither do we know much about its geometry, simply because our observatories are concentrated, for all practical purposes, vanishingly close to a single point in an immensity whose size can only be measured by the billions of years required by light to go from one extremity to another!