A flash bulb erupts, and you say cheese and pose with a rictus grin overrunning your lips. This photograph is a point in time, like anchors for memory, a remnant of the world as it once stood and a lighthouse guiding people back to an instant in the past. After the initial shock of that pulse of light, our eyes suffer a brief aftershock, Flash Blindness. A hit of illumination is quickly saturating the retinal pigment, so we see a greenish spot that floods our vision for up to a few minutes, almost as a sacrifice to the fleetingness of sight and events given over to a camera's snap. In a pattern often witnessed throughout reality, a common consequence of light is evident in the sky in every corner of existence. This pervasive interference is known as the Cosmic Microwave Background (CMB for short). CMB was first predicted by Ralph Alpher and Robert Herman in 1948 and confirmed in 1964 when discovered by Arno Penzias and Robert Woodrow Wilson. While using their radio telescope for radio astronomy purposes, Penzias and Wilson found a persistent hiss coming from everywhere in the sky their telescope pointed, first thinking that they were picking up interference, it soon transpired the sky itself transmitted the hiss. The CMB is a cool afterglow of the Big Bang, as a crude photo and in a way that's what it is. It is the earliest account we, the stardust of the beginning, have of the universe's birth, glancing back at our unified infancy.
Greater elegance at reading this leftover radiation has led us to estimate that the universe is over 13.8 billion years old. A beat after the Big Bang, CMB radiation remains to tell the tale of the rapid expansion and development of the cosmos, a story of how the universe is like a pop-up paper lamp bursting out. However, an anomaly in the CMB perplexes scientists; this oddity is a 1.8 billion light years wide cold spot. Some cosmologists believe that it could indicate that our early universe bumped into another. If universes can spring into life in a close vicinity, so close that they collide - pretty much as proto-planets do - is it possible that their birth originates from the same terminus point (in the same way that new stars spring from the nebulae of old ones?) Perhaps Dark Matter is so omnipresent because it stabilises universes and when a sufficient death of a universe occurs and rips apart, does it strain or react with Dark Matter enough to push through in a Singularity, resulting in a Big Bang?