Darkness and silence.
It was a step beyond mere darkness – there was no possibility of light anywhere. Indeed, there was no possibility of "anywhere" as you or I would know it.
Between universes, light and darkness, sound and silence, even time and space had no meaning. To be sure, there was distance of a sort – the math allowed for it. And things moved through it this distance, so there was something akin to the passing of time.
In the soundless, lightless void, immense sheets of nothingness rippled. Or maybe the sheets were tiny – with what would anyone compare them, even if there were anyone to make such a comparison? Tiny, or huge, these ghost sheets were sheets of nothingness that rippled past each other in the void. For the most part, they avoided each other, pushed away from each other by forces arising from the scattered charges and masses they happened to contain.
Sometimes, oh, so rarely, two of these ghost sheets would be too empty to push each other away, and they would come into contact. A gentle brush against each other, or a violent crash – it scarcely seems to matter. This contact had a profound effect on the ghostly sheets of emptiness involved. The delicate balance of nothingness was perturbed. As ghost pushed through ghost, the quiet emptiness was torn asunder. Where there had been void, the energy of the collision gave rise to twin opposites. Void gave birth to energy and space. Space splintered into countless dimensions, including the space and time we know today. Energy froze out into bits of matter, or diffused through the sudden roominess of space-time, filling it with a fiery glow.
This happened in a bare instant, and in that instant, the emptiness exploded in a fury of light and heat, of matter and energy, space and time. A universe was born.
In the next instant, the basic form of the universe was set. In the next few instants, it would develop in ways that set its final structure. Over millions, and then billions of years, the newborn universe would grow, mature, and develop. Life would arise on countless worlds. On a few of these worlds, intelligence would come to be. Where there was intelligence, there would eventually come to be curiosity, and these intelligences would wonder how their world came to be.
On these worlds, curiosity led to explanations. Some of them made sense, some others were fairly close to being true. A few seekers discovered, or deduced, the history of creation, and its birth in a fiery crash between ghosts of universes. Discovery after discovery led to an ever subtler understanding of the laws of the universe. A better understanding led to ever more discoveries, and so the cycle would continue. An yet, only a few of those who asked questions about the universe thought to ask about the other universe – the partner in the dance that gave rise to everything.
The meeting between these two ghosts made a lasting impression in both of them, and each would inevitably carry the traces. Perhaps it should not have been too surprising that a link between the two. Even though separated from each other for billions of years, they would continue to influence each other in surprising ways. Inevitably, the few who asked about the other universe would learn how to perceive it, and to affect it. Once that bridge was crossed, nothing would ever be the same again.